Body Control Modules Chevrolet Corvette C5

DESCRIPTION

The Body Control Module (BCM) communicates with the following systems over the serial data line to control various functions.

1. Powertrain Control Module (PCM)
2. Instrument Panel Cluster (IPC)
3. Real Time Damping (RTD)
4. Seat Control Module (SCM)
5. Left Door Control Module (LDCM)
6. Right Door Control Module (RDCM)
7. Remote Function Actuator (RFA)
8. Heating, Ventilation & Air Conditioning (HVAC)
9. Radio
10. Anti-lock Brake System (ABS)
11. Supplemental Inflatable Restraint (SIR)

Some vehicle systems share data over a serial data line to execute various vehicle functions. Communication between each system is accomplished by sending digitally coded messages, which consist of specific information the system module must follow. Each system module is assigned its own recognition code, so that it can respond to appropriate messages. The BCM acts as the power mode master and sends power mode messages on the serial data line. Power mode messages are ignition switch position. Systems not directly communicating with the ignition switch use the power mode messages to determine ignition switch position. Systems other than the BCM respond to the power mode messages with a State Of Health (SOH) code message. The SOH messages lets the BCM know that those systems can communicate with other systems.

OPERATION

The Body Control Module (BCM) has 2 main power feeds (high and low current) and 2 main grounds. Low power feed (battery 1) is used to supply power for BCM's logic and internal driver operation. Operating current at low power feed should not exceed 3 amps. High power feed is used to supply power for systems that draw higher amounts of current. Operating current at high power feed should not exceed 7.5 amps for 2 seconds when BCM is awake or 2.5 milliamps when BCM is asleep. For most functions, BCM system voltage should be 9-16 volts. If voltage exceeds 16 volts, BCM will disable functions that could be damaged.

If a BCM malfunction would result in unacceptable vehicle operation, BCM will take fail-soft action to minimize the condition (i.e., BCM will substitute a fixed input or output value if BCM is unable to interpret data).

MONITORED LOADS

The BCM can detect if certain electrical loads have been left on to minimize the possibility of battery rundown. When BCM detects that ignition has been turned off, BCM immediately checks status of load monitor input. If BCM detects that a load is present (ground on circuit No. 640), BCM will turn on load monitor relay for 15 minutes. If BCM detects load is still present after 15 minutes, BCM will turn off relay, removing battery voltage from loads. If a switch transition is detected by BCM, BCM will turn on relay again for another 15-minute period.

LOAD SHED CONTROL/INTERIOR LAMP OVER VOLTAGE PROTECTION

BCM can turn off rear window defogger and heated outside mirror electrical loads when vehicle is experiencing conditions that will allow these loads to discharge the battery. BCM will also turn off these loads if engine demands are higher. BCM will disable interior lights if system voltage exceeds 18 volts, in order to extend bulb life.

DRIVER IN VEHICLE DETECTION

By using the ignition switch and door ajar inputs, BCM can detect if driver has left the vehicle. If ignition is turned off and no door ajar status is detected, BCM assumes that driver is in vehicle. As soon as BCM receives a door ajar signal, it will assume that driver has left vehicle. This information is used for Retained Accessory Power (RAP) functions.

BODY CONTROL MODULE ASLEEP/WAKE-UP SIGNALS

Signals that activate the BCM are known as wake-up signals. BCM is asleep when it is not controlling or monitoring the following wake-up functions

1. Any activity on serial data line.
2. Hatch or door ajar switch.
3. Hatch release switch.
4. Key-in-ignition switch.
5. Monitored load relay.
6. Any exterior lighting function.
7. Battery disconnection and reconnection.
8. Ignition is turned on.

The BCM will enter asleep state when there is no activity on serial data line, ignition is turned off, no outputs are commanded, no delay timers are actively counting and no wake-up inputs are present.

Inputs

The following components provide direct input to BCM.

1. Ambient Light Signal
2. Column Feedback Switch
3. Door Ajar Switches
4. Fog Light Switch
5. Folding Top Ajar Switch
6. Folding Top Release Switch
7. Hatch Ajar Switch
8. Hatch Release Switch
9. Headlights OFF
10. Ignition Switch
11. Key In/Out Ignition Switch
12. Monitored Loads
13. Pass-Key Resistance
14. Rear Defogger Switch
15. Turn Signal Monitor
16. Traction Control Switch

Outputs

The following components are outputs controlled directly by the BCM.

1. Automatic Headlight Control
2. Console Light Dimming
3. Courtesy Light Relay
4. Daytime Running Light (DRL) Relays
5. Fog Light Relay
6. Folding Top Release Relay
7. Hatch Release Relay
8. Horn Relay
9. HVAC Light Dimming Control
10. Monitored Load Relay
11. PRNDL Light Control
12. Rear Defogger Relay

COMPONENT LOCATIONS

COMPONENT LOCATIONS

Scheme 1

Scheme 2

Scheme 3

PROGRAMMING

Note. Following procedure is written specifically for Tech 2 scan tool. A generic scan tool may not be capable of performing all necessary programming functions.

Note. If Body Control Module (BCM) is not properly configured, BCM will set default values for some systems, which may cause faults in other systems.

Body Control Module (BCM) Electronically Erasable Programmable Only Memory (EEPROM) chip must be programmed with proper Regular Production Options (RPO) configurations. EEPROM stores information about vehicle options and point of sale. When BCM is replaced, new BCM must be programmed to identify the following information.

1. Country Of Sale (US, Canada, Europe, Etc.)
2. Real Time Damping (F45)
3. Memory Options (AAB)
4. Front Fog Lights (T96)
5. HVAC (C60-Manual Or CJ2-Automatic)
6. Active Handling (JL4)
7. Automatic Headlight Control (T82)
8. Power Tilt/Telescoping Steering Column (N37)

Since BCM sends a password to PCM, PCM must also be programmed to accept the new password. BCM programming procedure will enable learn password mode for BCM and PCM (this mode allows PCM to learn new password sent by BCM whenever BCM or PCM is replaced). If BCM is not properly programmed, vehicle will exhibit a no-crank condition and PCM will set DTC P1631.

When BCM is replaced, BCM must be programmed to accept resistance value of existing vehicle keys so that it will allow PASS-Key® operation. New BCM is programmed to accept first PASS-Key® resistance value detected. If BCM is unable to detect a valid PASS-Key® resistance value, BCM will not end programming sequence and DTC 2735 will set.

Programming Procedure

Note. When programming procedure is performed, DTC P1631 will set in PCM (this is normal). When DTC P1631 sets, turn ignition off for 30 seconds, then turn ignition on. DTC P1631 should clear. If DTC P1631 does not clear, go to appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

Note. Maintain proper battery voltage during programming procedure and perform steps as specified, or programming procedure will have to be repeated.

1. Using scan tool, select NEW BCM SETUP. Program BCM with correct RPO code configuration.
2. Using scan tool, check for proper communication between BCM and PCM. If components cannot communicate, diagnose and repair problem as necessary. If BCM and PCM are communicating properly, go to next step.
3. Turn ignition on (engine off) for 11 minutes. Turn ignition off for 30 seconds. Turn ignition on (engine off) for 11 minutes. Turn ignition off for 30 seconds. Turn ignition on (engine off) for 11 minutes or until DTC P1631 sets. Turn ignition off for 30 seconds. Turn ignition on (engine off) for 30 seconds. Attempt to start engine. If engine starts and runs normally, system is okay. If engine does not start and run normally, perform on-board diagnostic system check. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

SELF-DIAGNOSTIC SYSTEM

Note. For wiring and connector terminal identification, see WIRING DIAGRAMS .

Note. When testing procedure indicates to probe or check a terminal, use adapters from Connector Test Adapter Kit (J-35616-A). This will ensure terminal will not be damaged and connection is okay.

Instrument Panel Cluster (IPC) is equipped with an on-board diagnostic display feature which can display and/or clear DTCs. When specific buttons on IPC are pressed, DTCs are displayed on IPC's 20-character Driver Information Center (DIC). See RETRIEVING DIAGNOSTIC TROUBLE CODES (DTCS) .

When diagnostic mode is first entered, IPC will enter an automatic display sequence of all systems that communicate on serial data line. After each system is displayed, DIC will display the number of DTCs (current or history) set in that system. At any time during this automatic display sequence, the manual diagnostic mode may be selected.

In manual diagnostic mode, a specific module can be manually selected for diagnosis by pressing specific buttons on Driver Information Center (DIC). Only DTCs for that particular module will be displayed until another system is requested.

In both diagnostic modes, systems will be displayed in the following order.

1. Powertrain Control Module (PCM)
2. Traction Control System (TCS)
3. Real Time Damping (RTD)
4. Body Control Module (BCM)
5. Instrument Panel Cluster (IPC)
6. Radio
7. Heater, Ventilation And Air Conditioning (HVAC)
8. Left Door Control Module (LDCM)
9. Right Door Control Module (RDCM)
10. Seat Control Module (SCM)
11. Remote Function Actuation (RFA)

If a DTC exists in any system, display will indicate whether DTC is current (with a "C") or history (with an "H"). When E/M button on DIC is pressed at any time, IPC will exit diagnostics mode. (Scheme 4) On-board diagnostics will also be exited automatically if no DIC buttons are pressed for 60 seconds.

Using On-Board Diagnostics

Turn ignition on (engine off). Press RESET button on Driver Information Center (DIC) to acknowledge any warning messages that may be present. (Scheme 4) Press OPTIONS button and hold. While holding OPTIONS button, press FUEL button 4 times within 10 seconds. System will enter automatic display mode.

In automatic display mode, each system module will be displayed on DIC followed by DTCs that exist in that module. If no DTCs exist, DIC will display NO CODES. If DTCs exist, each DTC will be displayed for 3 seconds followed by a one second pause. If Instrument Panel Cluster (IPC) cannot communicate with any system, DIC will display NO COMM for that system. At any time during automatic display mode, manual display feature can be activated by pressing any DIC button except E/M button. When all systems have been checked in automatic mode, DIC will display NO MORE CODES for 2 seconds, and will then enter manual mode.

When manual mode is entered, DIC will display MANUAL DIAGNOSTICS for 2 seconds or until any DIC button except E/M button is pressed. DIC will then display first system and number of DTCs set in that system, and wait for further instructions. Using DIC buttons, move through system diagnostics as necessary. See DIC BUTTON DIAGNOSTIC FUNCTIONS table. (Scheme 4) Note all codes displayed in Body Control Module (BCM) and proceed to appropriate diagnostic and repair procedure. See BODY CONTROL MODULE DIAGNOSTIC TROUBLE CODE DEFINITIONS table.

When E/M button on DIC is pressed at any time, IPC will exit diagnostics mode. On-board diagnostics will also be exited automatically if no DIC buttons are pressed for 60 seconds.

DIC BUTTON DIAGNOSTIC FUNCTIONS

Scheme 4

Using Scan Tool

Diagnostic Trouble Codes (DTCs) can also be retrieved using scan tool. Connect scan tool to Data Link Connector (DLC) located under driver's side of instrument panel. Turn ignition on. Select appropriate module on scan tool display to retrieve current and history DTCs. Record DTCs and proceed to appropriate DTC and follow diagnostic and repair procedures. See BODY CONTROL MODULE DIAGNOSTIC TROUBLE CODE DEFINITIONS table.

BODY CONTROL MODULE DIAGNOSTIC TROUBLE CODE DEFINITIONS

BODY CONTROL MODULE DIAGNOSTIC TROUBLE CODE DEFINITIONS

CLEARING DIAGNOSTIC TROUBLE CODES (DTCS)

Current DTCs will clear as soon as the fault is repaired and ignition switch is cycled to on and off position 50 times. History DTCs will need to be manually cleared using on-board diagnostics or scan tool.

Use manual control functions to select and view DTC. See RETRIEVING DIAGNOSTIC TROUBLE CODES (DTCS) . Depress the RESET button on Driver's Information Center (DIC) for 2 seconds to clear the selected DTC from the selected module.

Select CLEAR DTCs function on scan tool. Clear current and history DTCs. Operate vehicle and recheck for DTCs.

BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK

Note. Use this check as the starting point for any Body Control Module (BCM) complaint. BCM is a very reliable component, and is not likely the cause of malfunction. Most malfunctions are caused by faulty wiring, connectors or components.

1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). If scan tool powers up, go to next step. If scan tool does not power up, go to «SCAN TOOL DOES NOT POWER UP»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__scan-tool-does-not-power-up) .
2. Turn ignition on. Attempt to establish communication with BCM. If scan tool communicates with BCM, go to next step. If scan tool does not communicate with BCM, go to «SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) .
3. Check for BCM DTCs. If any BCM DTCs exist, go to next step. If no BCM DTCs exist, check for symptoms and go to appropriate article for symptom related diagnostic procedure.
4. Using scan tool, check for any DTCs that begin with "U" (communication DTCs) stored in BCM. If any communication DTCs exists, go to «SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If no communication DTCs exist in BCM, perform appropriate test under «DIAGNOSTIC TESTS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . See «BODY CONTROL MODULE DIAGNOSTIC TROUBLE CODE DEFINITIONS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) table.

Scheme 5

Testing

1. Connect scan tool to Data Link Connector (DLC) located under steering column. If scan tool powers up, go to next step. If scan tool does not power up, go to «SCAN TOOL DOES NOT POWER UP»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__scan-tool-does-not-power-up).
2. Turn ignition on. Attempt to communicate with following systems. Powertrain Control Module (PCM) Traction Control System (TCS) Real Time Damping (RTD) Body Control Module (BCM) Instrument Panel Cluster (IPC) Radio Heater, Ventilation and Air Conditioning (HVAC) Left Door Control Module (LDCM) Right Door Control Module (RDCM) Seat Control Module (SCM) Remote Function Actuation (RFA) Sensing and Diagnostic Module (SDM) If scan tool communicates with these systems, go to next step. If scan tool does not communicate with all systems, go to step 5.
3. Check for communication DTCs (communication DTCs begin with "U"). If any DTCs between U1000 and U1255 are set, go to next step. If no DTCs are set, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__diagnostic-aids).
4. If any system has communication DTCs U1000 or U1255 stored as current or history, go to «DTC U1000 & U1255: CLASS 2 COMMUNICATION MALFUNCTION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under DIAGNOSTIC TESTS. If any system has communication DTCs U1001 through U1254 stored as current or history, go to «DTC U1001-U1254: LOSS OF COMMUNICATION WITH XXX»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under DIAGNOSTIC TESTS.
5. Turn ignition off. Disconnect scan tool. Check for poor connections at DLC connector terminals No. 2 (Purple wire) and No. 5 (Black/White wire). (Scheme 6) If connections are okay, go to next step. If faulty connections are found, repair as necessary and go to diagnostic system check for module or system not communicating.
6. Check continuity in Black/White wire between DLC connector terminal No. 5 and ground. If circuit is okay, go to next step. If open circuit is found, repair as necessary and go to diagnostic system check for module or system not communicating.
7. Disconnect bus bars from Black 12-pin star connectors No. 1 and 2. See «COMPONENT LOCATIONS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__component-locations). Check for poor connections at star connectors. If connections are okay, go to next step. If faulty connections are found, repair as necessary and go to diagnostic system check for module or system not communicating.
8. Turn ignition off. Disconnect scan tool. Ensure bus bars are still disconnected from star connectors No. 1 and 2. Using DVOM, check continuity of Purple wire between DLC connector terminal No. 2 and star connector No. 1 terminal "A". If continuity exists, go to next step. If continuity does not exist, repair as necessary and go to diagnostic system check for module or system not communicating.
9. Turn ignition off. Connect scan tool. Ensure bus bars are still disconnected from star connectors No. 1 and 2. Connect Serial Data Link Tester (J-42236) to both star connectors. Ensure star connectors correctly correspond with serial data link testing connectors No. 1 and 2. Using serial data link tester, put switch in STAR CONNECTOR #1 position. Rotate rotary switch to "M" position. Turn ignition on. Using scan tool, attempt to establish communication with BCM. If scan tool communicates with BCM, go to next step. If scan tool does not communicate with BCM, go to step 12.
10. Ensure switch on serial data link tester is in STAR CONNECTOR #1 position. Using scan tool, attempt to establish communication with the following vehicle systems by rotating rotary switch on serial data link tester as specified: "L" Heating, Ventilation and Air Conditioning (HVAC) system (if equipped). "J" Remote Function Actuator (RFA) system. "H" Real Time Damping (RTD) system (if equipped). "G" Instrument Panel Cluster (IPC). "E" Traction Control System (TCS). "D" Radio system. "B" Powertrain Control Module (PCM). If scan tool communicates with each system, go to next step. If scan tool does not communicate with each system, go to step 12.
11. Turn switch on serial data link tester to STAR CONNECTOR #2 position. Using scan tool, attempt to establish communication with the following vehicle systems by rotating rotary switch on serial data link tester as specified: "C" Left Door Control Module (DCM) system. "D" Right Door Control Module (DCM) system. "K" Seat Control Module (SCM) system (if equipped). If scan tool does not communicate with each system, go to next step. If scan tool communicates with each system, go to step 15.
12. Turn ignition off. Disconnect appropriate system module for system that did not communicate with scan tool. Using DVOM, check for short to ground or short to voltage in circuit between appropriate terminals on appropriate star connector and appropriate system module connectors. See «SERIAL DATA LINE IDENTIFICATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) table. If circuits are okay, go to next step. If faulty circuit is found, repair as necessary and go to step 15.
13. Check for poor connections at serial data line terminals for system that did not communicate with scan tool. If connections are okay, go to next step. If faulty connections are found, repair as necessary and go to step 15.
14. Replace appropriate module for system that did not communicate with scan tool. After repairs, go to next step.
15. Turn ignition off. Reinstall all components or connectors. Connect scan tool to DLC located under steering column. Turn ignition on. Wait 10 seconds for scan tool to power up. Display DTCs for each module. If any communication DTCs are set (communication DTCs begin with "U") and current, go to step 17. If no communication DTCs are set (communication DTCs begin with "U") or are set as history, go to next step.
16. If any DTCs are set that do not begin with "U", go to next step. If no DTCs are set, go to step 19.
17. Go to appropriate diagnostic and repair procedure for DTC under «DIAGNOSTIC TESTS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules). If sent here from another article, return to that article and repair DTC under DIAGNOSTIC TESTS. After repairs, go to next step.
18. If all DTCs are diagnosed and repaired, go to next step. If all DTCs are not diagnosed and repaired, go to step 17.
19. Using scan tool, clear all DTCs.

SERIAL DATA LINE IDENTIFICATION

Diagnostic Aids

When class 2 serial data line is shorted to ground, U1300 will be set. Go to DTC U1300: SERIAL DATA LINE SHORT TO GROUND under DIAGNOSTIC TESTS. When class 2 serial data line is shorted to voltage, U1301 will be set. Go to DTC U1301: SERIAL DATA LINE SHORT TO BATTERY under DIAGNOSTIC TESTS. Disconnecting modules and turning the ignition switch to RUN may cause DTCs to set in these modules. Check for DTCs in each module after repair.

Scheme 6

SCAN TOOL DOES NOT POWER UP

1. Measure voltage at Data Link Connector (DLC) terminal No. 16 (Orange wire). (Scheme 6) If battery voltage is present, go to next step. If battery voltage is not present, repair open or short to ground in Orange wire. After repairs, recheck scan tool operation.
2. Check continuity between DLC terminal No. 4 (Black wire) and ground. If continuity exists, go to next step. If continuity does not exist, repair Black wire as necessary and recheck scan tool operation.
3. Check for poor connections between scan tool and DLC terminals No. 4 and No. 16. If connections are okay, go to next step. If poor connections are found, repair as necessary and recheck scan tool operation.
4. Scan tool may be malfunctioning. Check scan tool manual for diagnostic procedures. After repairs, recheck operation of scan tool.

When Body Control Module (BCM) receives a defogger on request from rear defogger switch with engine running, BCM will ground White wire to energize rear defogger relay. BCM monitors voltage level on rear defogger relay control circuit. When BCM activates rear defogger relay, voltage level in rear defogger relay control circuit should be low. When relay is not activated, voltage level in rear defogger relay control circuit should be high.

DTC B0432 will set when BCM detects a low voltage level in White wire for 2 seconds when it is not energizing rear defogger relay. No driver warning message will be displayed.

DTC B0432 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0432 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B0432 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command rear defogger relay on and off. If rear defogger relay does not turn on and off with commands, go to next step. If rear defogger relay turns on and off with commands, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules).
3. Turn ignition off. Remove rear defogger relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Using a test light connected to ground, probe rear defogger relay IGN terminal at instrument panel electrical center. If test light comes on, go to next step. If test light does not come on, go to step 10.
4. Connect test light between rear defogger relay IGN and CK193 terminals at instrument panel electrical center. Using scan tool, command rear defogger relay on and off. If test light does not turn on and off as commanded, go to next step. If test light turns on and off as commanded, go to step 8.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for an open in White wire between BCM connector C2 and rear defogger relay. See «WIRING DIAGRAMS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules). If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in White wire between BCM connector C2 and rear defogger relay. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at rear defogger relay terminals. If connections are okay, go to step 11. If problem is found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem is found and repaired, go to step 13.
10. Repair open or short in ignition feed circuit to instrument panel electrical center. See POWER DISTRIBUTION article in WIRING DIAGRAMS. After repairs, go to step 13.
11. Replace rear defogger relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to ground or open in White wire between BCM and rear defogger relay.
2. Poor connections at BCM, instrument panel electrical center or rear defogger relay.
3. Internal open or short in rear defogger relay.

If White wire between BCM and rear defogger relay is shorted to ground, rear defogger will stay on at all times. If White wire between BCM and rear defogger relay is open, rear defogger will stay off at all times.

Scheme 7

When Body Control Module (BCM) receives a defogger on request from rear defogger switch with engine running, BCM will ground White wire to energize rear defogger relay. BCM monitors voltage level on rear defogger relay control circuit. When BCM activates rear defogger relay, voltage level in rear defogger relay control circuit should be low. When relay is not activated, voltage level in rear defogger relay control circuit should be high.

DTC B0433 will set when BCM detects a high voltage level in White wire for 2 seconds when it is energizing rear defogger relay. No driver warning message will be displayed.

DTC B0433 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0433 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B0433 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command rear defogger relay on and off. If rear defogger relay does not turn on and off with commands, go to next step. If rear defogger relay turns on and off with commands, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules).
3. Turn ignition off. Remove rear defogger relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Using a test light connected to ground, probe rear defogger relay IGN terminal at instrument panel electrical center. If test light comes on, go to next step. If test light does not come on, go to step 10.
4. Connect test light between rear defogger relay IGN and CK193 terminals at instrument panel electrical center. Using scan tool, command rear defogger relay on and off. If test light does not turn on and off as commanded, go to next step. If test light turns on and off as commanded, go to step 8.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for short to voltage in White wire between BCM connector C2 and rear defogger relay. See «WIRING DIAGRAMS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules). If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in White wire between BCM connector C2 and rear defogger relay. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at rear defogger relay terminals. If connections are okay, go to step 11. If problem is found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem is found and repaired, go to step 13.
10. Repair open or short in ignition feed circuit to instrument panel electrical center. See POWER DISTRIBUTION article in WIRING DIAGRAMS. After repairs, go to step 13.
11. Replace rear defogger relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to 2.

The following conditions may cause an intermittent

1. Intermittent short to voltage in White wire between BCM and rear defogger relay.
2. Poor connections at BCM, instrument panel electrical center or rear defogger relay.
3. Internal short to voltage in rear defogger relay.

If White wire between BCM and rear defogger relay is shorted to voltage or if BCM is open internally, rear defogger will stay off at all times.

Body Control Module (BCM) grounds Light Green wire to energize right Daytime Running Lights (DRL) relay and right front turn signal. This allows right front turn signal to be used in DRL, Underhood Theft Deterrent (UTD) and approach lighting functions.

BCM monitors voltage level on Light Green wire. When BCM activates right DRL relay, voltage level in right DRL relay control circuit should be low. When relay is not activated, voltage level in right DRL relay control circuit should be high.

DTC B0502 will set when BCM detects a low voltage level in Light Green wire for 2 seconds when it is not energizing right DRL relay. No driver warning message will be displayed.

DTC B0502 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0502 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B0502 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command right Daytime Running Lights (DRL) relay on and off. If right DRL relay does not turn on and off with commands, go to next step. If right DRL relay turns on and off with commands, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules).
3. Turn ignition off. Remove right DRL relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Using a test light connected to ground, probe right DRL relay battery feed terminals at instrument panel electrical center. If test light comes on at both terminals, go to next step. If test light does not come on at both terminals, go to step 10.
4. Connect test light between right DRL relay battery feed and CKT 1966 terminals at instrument panel electrical center. Using scan tool, command right DRL relay on and off. If test light does not turn on and off as commanded, go to next step. If test light turns on and off as commanded, go to step 8.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for an open in Light Green wire between BCM connector C2 and right DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in Light Green wire between BCM connector C2 and right DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at right DRL relay terminals. If connections are okay, go to step 11. If problem is found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If problem was found and repaired, go to step 13. If connections are okay, go to step 12.
10. Repair open or short in battery feed circuit to instrument panel electrical center. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. After repairs, go to step 13.
11. Replace right DRL relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to ground or open in Light Green wire between Body Control Module (BCM) and right Daytime Running Lights (DRL) relay
2. Poor connections at BCM, instrument panel electrical center or right DRL relay
3. Internal open or short in right DRL relay.

If Light Green wire between BCM and right DRL relay is shorted to ground, right DRL will stay on at all times. If Light Green wire between BCM and right DRL relay is open, right DRL will stay off at all times.

Body Control Module (BCM) grounds Light Green wire to energize right Daytime Running Lights (DRL) relay and right front turn signal. This allows right front turn signal to be used in DRL, Underhood Theft Deterrent (UTD) and approach lighting functions.

BCM monitors voltage level on Light Green wire. When BCM activates right DRL relay, voltage level in right DRL relay control circuit should be low. When relay is not activated, voltage level in right DRL relay control circuit should be high.

DTC B0503 will set when BCM detects a high voltage level in Light Green wire for 2 seconds when it is energizing right DRL relay. No driver warning message will be displayed.

DTC B0503 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0503 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B0503 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command right Daytime Running Lights (DRL) relay on and off. If right DRL relay does not turn on and off with commands, go to next step. If right DRL relay turns on and off with commands, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules).
3. Turn ignition off. Remove right DRL relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Using a test light connected to ground, probe right DRL relay battery feed terminals at instrument panel electrical center. If test light comes on at both terminals, go to next step. If test light does not come on at both terminals, go to step 10.
4. Connect test light between right DRL relay battery feed and CKT 1966 terminals at instrument panel electrical center. Using scan tool, command right DRL relay on and off. If test light does not turn on and off as commanded, go to next step. If test light turns on and off as commanded, go to step 8.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for short to voltage in Light Green wire between BCM connector C2 and right DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If faulty circuit is found and repaired, go to step 13. If circuit is okay, go to step 9.
7. Check for short to ground in Light Green wire between BCM connector C2 and right DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If faulty circuit is found and repaired, go to step 13. If circuit is okay, go to step 9.
8. Check for poor connections at right DRL relay terminals. If connections are okay, go to step 11. If problem is found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem is found and repaired, go to step 13.
10. Repair open or short in battery feed circuit to instrument panel electrical center. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. After repairs, go to step 13.
11. Replace right DRL relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to voltage in Light Green wire between Body Control Module (BCM) and right Daytime Running Lights (DRL) relay.
2. Poor connections at BCM, instrument panel electrical center or right DRL relay.
3. Internal short to voltage in right DRL relay.

If Light Green wire between BCM and right DRL relay is shorted to voltage or if BCM is open internally, right DRL will stay off at all times.

Body Control Module (BCM) grounds Orange/Black wire to energize left Daytime Running Lights (DRL) relay and left front turn signal. This allows left front turn signal to be used in DRL, Underhood Theft Deterrent (UTD) and approach lighting functions.

BCM monitors voltage level on Orange/Black wire. When BCM activates left DRL relay, voltage level in left DRL relay control circuit should be low. When relay is not activated, voltage level in left DRL relay control circuit should be high.

DTC B0507 will set when BCM detects a low voltage level in Orange/Black wire for 2 seconds when it is not energizing left DRL relay. No driver warning message will be displayed.

DTC B0507 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0507 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B0507 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command left Daytime Running Lights (DRL) relay on and off. If left DRL relay does not turn on and off with commands, go to next step. If left DRL relay turns on and off with commands, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules).
3. Turn ignition off. Remove left Daytime Running Lights (DRL) relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Using a test light connected to ground, probe left DRL relay battery feed terminals at instrument panel electrical center. If test light comes on at both terminals, go to next step. If test light does not come on at both terminals, go to step 10.
4. Connect test light between left DRL relay battery feed and CKT 1976 terminals at instrument panel electrical center. Using scan tool, command left DRL relay on and off. If test light does not turn on and off as commanded, go to next step. If test light turns on and off as commanded, go to step 8.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for an open in Orange/Black wire between BCM connector C3 and left DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in Orange/Black wire between BCM connector C3 and left DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at left DRL relay terminals. If connections are okay, go to step 11. If problem was found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem is found and repaired, go to step 13.
10. Repair open or short in battery feed circuit to instrument panel electrical center. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. After repairs, go to step 13.
11. Replace left DRL relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to ground or open in Orange/Black wire between BCM and left DRL relay.
2. Poor connections at BCM, instrument panel electrical center or left DRL relay.
3. Internal open or short in left DRL relay.

If Orange/Black wire between BCM and left DRL relay is shorted to ground, left DRL will stay on at all times. If Orange/Black wire between BCM and left DRL relay is open, left DRL will stay off at all times.

Body Control Module (BCM) grounds Orange/Black wire to energize left Daytime Running Lights (DRL) relay and left front turn signal. This allows left front turn signal to be used in DRL, Underhood Theft Deterrent (UTD) and approach lighting functions.

BCM monitors voltage level on Orange/Black wire. When BCM activates left DRL relay, voltage level in left DRL relay control circuit should be low. When relay is not activated, voltage level in left DRL relay control circuit should be high.

DTC B0508 will set when BCM detects a high voltage level in Orange/Black wire for 2 seconds when it is energizing left DRL relay. No driver warning message will be displayed.

DTC B0508 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0508 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B0508 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command left DRL relay on and off. If left DRL relay does not turn on and off with commands, go to next step. If left DRL relay turns on and off with commands, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules).
3. Turn ignition off. Remove left Daytime Running Lights (DRL) relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Using a test light connected to ground, probe left DRL relay battery feed terminals at instrument panel electrical center. If test light comes on at both terminals, go to next step. If test light does not come on at both terminals, go to step 10.
4. Connect test light between left DRL relay battery feed and CKT 1976 terminals at instrument panel electrical center. Using scan tool, command left DRL relay on and off. If test light turns on and off as commanded, go to step 8. If test light does not turn on and off as commanded, go to next step.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for short to voltage in Orange/Black wire between BCM connector C3 and left DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in Orange/Black wire between BCM connector C3 and left DRL relay. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at left DRL relay terminals. If connections are okay, go to step 11. If problem was found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem was found and repaired, go to step 13.
10. Repair open or short in battery feed circuit to instrument panel electrical center. See HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article. After repairs, go to step 13.
11. Replace left DRL relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to voltage in Orange/Black wire between BCM and left DRL relay.
2. Poor connections at BCM, instrument panel electrical center or left DRL relay.
3. Internal short to voltage in left DRL relay.

If Orange/Black wire between BCM and left DRL relay is shorted to voltage or if BCM is open internally, left DRL will stay off at all times.

Body Control Module (BCM) calibrations are stored in Electronically Erasable Programmable Read Only Memory (EEPROM). When ignition is first turned on, BCM performs internal tests on EEPROM and determines integrity of its non-volatile memory. BCM then compares this checksum with previously stored checksum. DTC B0605 will set when stored checksum does not match calculated checksum or BCM detects an internal memory malfunction (checksum error). This condition will only occur when ignition is first turned on. No driver warning message will be displayed.

DTC B0605 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B0605 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING.

Since EEPROM cannot be removed from BCM and DTC B0605 is an internal BCM malfunction, BCM must be replaced.

This fault is contained inside of the control module. No external circuits are used. DTC will set when control module detects an internal write or check sum error. When DTC sets, the microprocessor refuses all additional inputs. A current DTC will clear when microprocessor successfully writes to EEPROM. A history DTC will clear after 100 fault-free ignition cycles. DTC can also be cleared using Instrument Panel Cluster (IPC) or scan tool.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING.

DTC may be stored as history without affecting operation of control module. If DTC is stored as history and not retrieved as current, DO NOT replace control module. If DTC is set as current and history, replace control module.

Front foglight switch supplies a direct battery input to Body Control Module (BCM) when switch is pressed. This input allows BCM to detect a front foglight switch on or off request. If BCM detects battery voltage on front foglight Orange/Black wire when front foglights are off, BCM will energize front foglight relay to turn front foglights on. If BCM detects battery voltage after front foglights on command, BCM will turn off front foglights. BCM monitors Orange/Black wire to determine how long voltage is applied.

DTC B2403 will set when BCM detects battery voltage on Orange wire for longer than 60 seconds. No driver warning message will be displayed. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2403 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2403 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Select BCM DATA LIST on scan tool and monitor FRONT FOG LIGHT SWITCH status. If FRONT FOG LIGHT SWITCH status is INACTIVE, go to next step. If FRONT FOG LIGHT SWITCH status is not INACTIVE, go to step 4 .
3. Monitor FRONT FOG LIGHT SWITCH status. Activate front fog lights using switch. If FRONT FOG LIGHT SWITCH status changes, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If FRONT FOG LIGHT SWITCH status does not change, go to next step.
4. Turn ignition off. Remove front foglight switch and disconnect connector. Turn ignition on. Monitor FRONT FOG LAMP SWITCH status. If FRONT FOG LIGHT SWITCH status is not INACTIVE, go to next step. If FRONT FOG LIGHT SWITCH status is INACTIVE, go to step 7 .
5. Check for short to voltage in Orange/Black wire between BCM connector C2 terminal D4 and front foglight switch. If circuit is okay, go to next step. If faulty circuit is found and repaired, go to step 10 .
6. Check for poor connections at BCM connectors. If connections are okay, go to step 8 . If faulty connections are found and repaired, go to step 10 .
7. Check for poor connections at front fog light switch connector. If connections are okay, go to step 9 . If faulty connections are found and repaired, go to step 10 .
8. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to step 10 .
9. Replace front foglight switch. See «FOGLIGHT/REAR HATCH SWITCH»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__foglightrear-hatch-switch) under REMOVAL & INSTALLATION. After repairs, go to next step.
10. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2 .

The following conditions may cause an intermittent

1. Intermittent short to voltage in Orange/Black wire between BCM and foglight switch.
2. Foglight switch sticking or internally shorted to voltage.
3. Front foglight switch is pressed for longer than 60 seconds.

If Orange/Black wire between BCM and front foglight switch is shorted to voltage, front foglights will stay on or off at all times depending on which state they were in when malfunction occurred. If short to voltage occurred when front foglights were on, front foglights will remain off at all times. If short to voltage occurred when front foglights were off, front foglights will remain on at all times. BCM will retain this information even if ignition is turned off.

DTC B2408: REAR FOGLIGHT SWITCH CIRCUIT (SHORT TO VOLTAGE)

Note. This DTC applies only to export vehicles.

Rear foglight switch supplies a direct battery input to Body Control Module (BCM) when switch is pressed. This input allows BCM to detect a rear foglight switch on or off request. If BCM detects battery voltage on rear foglight Light Blue wire when rear foglights are off, BCM will energize rear foglight relay to turn rear foglights on. If BCM detects battery voltage after rear foglights on command, BCM will turn off rear foglights. BCM monitors Light Blue wire to determine how long voltage is applied.

DTC B2408 will set when BCM detects battery voltage on Light Blue wire for longer than 60 seconds. No driver warning message will be displayed. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2408 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2408 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Select BCM input display on scan tool and monitor REAR FOG LIGHT SWITCH status. If REAR FOG LIGHT SWITCH status is INACTIVE, go to next step. If REAR FOG LIGHT SWITCH status is not INACTIVE, go to step 4 .
3. Monitor REAR FOG LIGHT SWITCH status. Activate rear fog lights using switch. If REAR FOG LIGHT SWITCH status changes, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If REAR FOG LIGHT SWITCH status does not change, go to next step.
4. Turn ignition off. Remove rear foglight switch and disconnect connector. Turn ignition on. Monitor REAR FOG LAMP SWITCH status. If REAR FOG LIGHT SWITCH status is INACTIVE, go to next step. If REAR FOG LIGHT SWITCH status is not INACTIVE, go to step 7 .
5. Check for short to voltage in Light Blue wire between BCM connector C2 terminal D5 and rear foglight switch. If circuit is okay, go to next step. If faulty circuit is found and repaired, go to step 10 .
6. Check for poor connections at BCM connectors. If connections are okay, go to step 8 . If faulty connections are found and repaired, go to step 10 .
7. Check for poor connections at rear fog light switch connector. If connections are okay, go to step 9 . If faulty connections are found and repaired, go to step 10 .
8. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to step 10 .
9. Replace rear foglight switch. See «FOGLIGHT/REAR HATCH SWITCH»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__foglightrear-hatch-switch) under REMOVAL & INSTALLATION. After repairs, go to next step.
10. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2 .

The following conditions may cause an intermittent

1. Intermittent short to voltage in Light Blue wire between BCM and rear foglight switch.
2. Rear foglight switch sticking or internally shorted to voltage.
3. Rear foglight switch is pressed for longer than 60 seconds.

If Light Blue wire between BCM and rear foglight switch is shorted to voltage, rear foglights will stay on or off at all times depending on which state they were in when malfunction occurred. If short to voltage occurred when rear foglights were on, rear foglights will remain off at all times. If short to voltage occurred when rear foglights were off, rear foglights will remain on at all times. BCM will retain this information even if ignition is turned off.

Body Control Module (BCM) grounds Dark Blue wire to energize back-up light relay, which will turn back-up lights on. This allows back-up lights to be used in Underhood Theft Deterrent (UTD) and approach lighting functions.

BCM monitors voltage level in Dark Blue wire. When BCM activates back-up light relay, voltage level in back-up light relay control circuit should be low. When relay is not activated, voltage level in back-up light relay control circuit should be high.

DTC B2482 will set when BCM detects a low voltage level in Dark Blue wire for 2 seconds when it is not energizing back-up light relay. No driver warning message will be displayed.

DTC B2482 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2482 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2482 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command back-up light relay on and off. If back-up light relay turns on and off when commanded, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules). If back-up light relay does not turn on and off when commanded, go to next step.
3. Turn ignition off. Remove back-up light relay from underhood electrical center. (Scheme 8) Turn ignition on. Using a test light connected to ground, probe back-up light relay BATT terminals at underhood electrical center. If test light comes on at both terminals, go to next step. If test light does not come on at both terminals, go to step 10.
4. Connect test light between back-up light relay BATT and CKT 38 terminals at instrument panel electrical center. Using scan tool, command back-up light relay on and off. If test light does not turn on and off as commanded, go to next step. If test light turns on and off as commanded, go to step 8.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for an open in Dark Blue wire between BCM connector C2 terminal C1 and back-up light relay. See BACK-UP LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in Dark Blue wire between BCM connector C2 terminal C1 and back-up light relay. See BACK-UP LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at back-up light relay terminals. If connections are okay, go to step 11. If problem is found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem is found and repaired, go to step 13.
10. Repair open or short in appropriate battery feed circuit to underhood electrical center. See POWER DISTRIBUTION article in WIRING DIAGRAMS. After repairs, go to step 13.
11. Replace back-up light relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to ground or open in Dark Blue wire between BCM and back-up light relay.
2. Poor connections at BCM, underhood electrical center, or back-up light relay.
3. Internal open or short in back-up light relay.

If Dark Blue wire between BCM and back-up light relay is shorted to ground, back-up lights will stay on at all times. If Dark Blue wire between BCM and back-up light relay is open, back-up lights will stay off at all times.

Scheme 8

Body Control Module (BCM) grounds Dark Blue wire to energize back-up light relay, which will turn back-up lights on. This allows back-up lights to be used in Underhood Theft Deterrent (UTD) and approach lighting functions.

BCM monitors voltage level in Dark Blue wire. When BCM activates back-up light relay, voltage level in back-up light relay control circuit should be low. When relay is not activated, voltage level in back-up light relay control circuit should be high.

DTC B2483 will set when BCM detects a high voltage level in Dark Blue wire for 2 seconds when it is energizing back-up light relay. No driver warning message will be displayed.

DTC B2483 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2483 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2483 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, command back-up light relay on and off. If back-up light relay turns on and off when commanded, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules). If back-up light relay does not turn on and off when commanded, go to next step.
3. Turn ignition off. Remove back-up light relay from underhood electrical center. (Scheme 8) Turn ignition on. Using a test light connected to ground, probe back-up light relay BATT terminals at underhood electrical center. If test light comes on at both terminals, go to next step. If test light does not come on at both terminals, go to step 10.
4. Connect test light between back-up light relay BATT and CKT 38 terminals at instrument panel electrical center. Using scan tool, command back-up light relay on and off. If test light turns on and off as commanded, go to step 8. If test light does not turn on and off as commanded, go to next step.
5. If test light does not remain on with each command, go to next step. If test light remains on with each command, go to step 7.
6. Check for short to voltage in Dark Blue wire between BCM connector C2 terminal C1 and back-up light relay. See BACK-UP LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
7. Check for short to ground in Dark Blue wire between BCM connector C2 terminal C1 and back-up light relay. See BACK-UP LIGHTS article. If circuit is okay, go to step 9. If faulty circuit is found and repaired, go to step 13.
8. Check for poor connections at back-up light relay terminals. If connections are okay, go to step 11. If problem is found and repaired, go to step 13.
9. Check for poor connections at BCM connector terminals. If connections are okay, go to step 12. If problem is found and repaired, go to step 13.
10. Repair open or short in appropriate battery feed circuit to underhood electrical center. See POWER DISTRIBUTION article in WIRING DIAGRAMS. If a fuse is open, repair short in appropriate circuit. After repairs, go to step 13.
11. Replace back-up light relay. After repairs, go to step 13.
12. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
13. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to voltage in Dark Blue wire between BCM and back-up light relay.
2. Poor connections at BCM, underhood electrical center, or back-up light relay.
3. Internal short to voltage in back-up light relay.

If Dark Blue wire between BCM and back-up light relay is shorted to voltage or if BCM is open internally, back-up light will stay off at all times.

Body Control Module (BCM) monitors right front turn signal circuit to determine status of turn signal switch. When BCM detects an oscillating voltage on Dark Blue wire, BCM interprets this as a request from turn signal switch to turn right front turn signal on. The BCM then stops energizing right DRL relay, which disables right front turn signal light from DRL circuit, so that right front turn signal light will now flash. The BCM monitors Dark Blue wire to determine how long voltage is applied.

DTC B2578 will set when BCM detects continuous battery voltage in Dark Blue wire for longer than 5 seconds. No driver warning message will be displayed.

DTC B2578 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2578 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2578 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

Note. To identify wire colors for turn signals, see EXTERIOR LIGHTS article.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ignition on. Using scan tool, check for DTC B2583. If DTC B2583 also exists, go to step 10. If DTC B2583 does not also exist, go to next step.
3. Turn ignition off. Remove right Daytime Running Light (DRL) relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Turn right turn signals on. Using a test light connected to ground, probe right DRL relay CKT 15 at instrument panel electrical center. If test light flashes, go to step 13. If test light does not flash, go to next step.
4. If test light stays on, go to next step. If test light does not stay on, diagnose inoperative turn signals. See EXTERIOR LIGHTS article.
5. Disconnect turn signal switch (multifunction switch) connector. See «STEERING COLUMN SWITCHES - CORVETTE»(/chevrolet/corvette/c5-1997-2004/remont/steering-column-switches/#steering-column-switches) article. If test light remains on, go to next step. If test light turns off, go to step 9.
6. Disconnect hazard warning switch connector. See «ANALOG INSTRUMENT PANELS - CORVETTE»(/chevrolet/corvette/c5-1997-2004/remont/gauges-instrument-panels/#analog-instrument-panels) article. If test light remains on, go to next step. If test light turns off, go to step 10.
7. Disconnect instrument cluster connector. If test light remains on, go to next step. If test light turns off, go to step 11.
8. Disconnect Body Control Module (BCM) connector. See «COMPONENT LOCATIONS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__component-locations). If test light remains on, go to step 12. If test light turns off, go to step 14.
9. Repair short to voltage in Dark Blue wire between turn signal switch connector terminal "F" and right Daytime Running Light (DRL) relay located in instrument panel electrical center. See EXTERIOR LIGHTS article. After repairs, go to step 15.
10. Repair short to voltage in Dark Blue wire between hazard warning switch connector terminal "G" and right DRL relay. See EXTERIOR LIGHTS article. After repairs, go to step 15.
11. Repair short to voltage in Dark Blue wire between instrument cluster connector terminal A16 and right DRL relay. See EXTERIOR LIGHTS article. After repairs, go to step 15.
12. Repair short to voltage in Dark Blue wire between BCM connector C2 terminal D7 and right DRL relay. See EXTERIOR LIGHTS article. After repairs, go to step 15.
13. Replace right DRL relay. After repairs, go to step 15.
14. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
15. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to voltage in Dark Blue wire between BCM connector C2 and instrument panel electrical center connector C2, Purple wire between hazard warning switch and turn signal switch or Dark Blue/White wire between instrument panel electrical center connector C2 and right front turn signal light.
2. Turn signal switch or hazard warning switch sticking or internally shorted.

BCM needs to detect voltage oscillation in Dark Blue wire in order to deactivate right front turn signal relay. If BCM detects continuous battery voltage, it is interpreted as a short to voltage. BCM will continue normal DRL operation, and right front turn signal will be inoperative.

Body Control Module (BCM) monitors left front turn signal circuit to determine status of turn signal switch. When BCM detects an oscillating voltage on Light Blue wire, BCM interprets this as a request from turn signal switch to turn left front turn signal on. The BCM then stops energizing left DRL relay, which disables left front turn signal light from DRL circuit, so that left front turn signal light will now flash. The BCM monitors Light Blue wire to determine how long voltage is applied.

DTC B2583 will set when BCM detects continuous battery voltage on Light Blue wire for longer than 5 seconds. No driver warning message will be displayed.

DTC B2583 requires an ignition cycle to change from current to history. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2583 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2583 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

Note. To identify wire colors for turn signals, see EXTERIOR LIGHTS article.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ignition on. Using scan tool, check for DTC B2583. If DTC B2583 also exists, go to step 10. If DTC B2583 does not also exist, go to next step.
3. Turn ignition off. Remove left Daytime Running Light (DRL) relay from instrument panel electrical center. (Scheme 7) Turn ignition on. Turn left turn signal on. Using a test light connected to ground, probe left DRL relay CKT 14 at instrument panel electrical center. If test light flashes, go to step 13. If test light does not flash, go to next step.
4. If test light stays on, go to next step. If test light does not stay on, diagnose inoperative turn signals. See EXTERIOR LIGHTS article.
5. Disconnect turn signal switch (multifunction switch) connector. See «STEERING COLUMN SWITCHES - CORVETTE»(/chevrolet/corvette/c5-1997-2004/remont/steering-column-switches/#steering-column-switches) article. If test light remains on, go to next step. If test light turns off, go to step 9.
6. Disconnect hazard warning switch connector. See «ANALOG INSTRUMENT PANELS - CORVETTE»(/chevrolet/corvette/c5-1997-2004/remont/gauges-instrument-panels/#analog-instrument-panels) article. If test light remains on, go to next step. If test light turns off, go to step 10.
7. Disconnect instrument cluster connector. If test light remains on, go to next step. If test light turns off, go to step 11.
8. Disconnect Body Control Module (BCM) connector. See «COMPONENT LOCATIONS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__component-locations). If test light remains on, go to step 12. If test light turns off, go to step 14.
9. Repair short to voltage in Light Blue wire between turn signal switch connector terminal "G" and left DRL relay located in instrument panel electrical center. See EXTERIOR LIGHTS article. After repairs, go to step 15.
10. Repair short to voltage in Light Blue wire between hazard warning switch connector terminal "F" and left DRL relay. See EXTERIOR LIGHTS article. After repairs, go to step 15.
11. Repair short to voltage in Light Blue wire between instrument cluster connector terminal A15 and left DRL relay. See EXTERIOR LIGHTS article. After repairs, go to step 15.
12. Repair short to voltage in Light Blue wire between BCM connector C2 terminal D8 and left DRL relay. See EXTERIOR LIGHTS article. After repairs, go to step 15.
13. Replace left DRL relay. After repairs, go to step 15.
14. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
15. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2.

The following conditions may cause an intermittent

1. Intermittent short to voltage in Light Blue wire between BCM connector C2 and instrument panel electrical center connector C1, Purple wire between hazard warning switch and turn signal switch or Light Blue/White wire between instrument panel electrical center connector C1 and left front turn signal light.
2. Turn signal switch or hazard warning switch sticking or internally shorted.

BCM needs to detect voltage oscillation in Light Blue wire in order to deactivate left front DRL relay. If BCM detects continuous battery voltage, it is interpreted as a short to voltage. BCM will continue normal DRL operation, and left front turn signal will be inoperative.

Traction control/suspension switch control circuit provides a ground input to Body Control Module (BCM) when switch is pressed. If BCM detects a ground on Brown/White wire when TCS is off, BCM will send signal on serial data line to Electronic Brake Traction Control Module (EBTCM) to turn on TCS. If BCM detects a ground when traction control system is on, BCM will send signal to EBTCM to turn off traction control system. BCM monitors traction control/suspension switch control circuit to determine how long a ground has been applied.

DTC B2597 will set when BCM detects a ground in Brown/White wire for longer than 60 seconds. If vehicle speed is detected, PCM may disable fuel supply to engine. No driver warning message will be displayed. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2597 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2597 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, select BCM INPUTS and monitor TCS SWITCH status. If TCS SWITCH status is INACTIVE, go to next step. If TCS SWITCH status is not INACTIVE, go to step 4 .
3. Activate TCS switch on center console. Monitor TCS SWITCH status on scan tool. If TCS SWITCH status changes, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If TCS SWITCH status does not change, go to next step.
4. Turn ignition off. Disconnect TCS switch connector. Turn ignition on. Monitor TCS SWITCH status on scan tool. If TCS SWITCH status is not INACTIVE, go to next step. If TCS SWITCH status is INACTIVE, go to step 7 .
5. Check for short to ground in Brown/White wire between BCM connector C2 and TCS switch. If circuit is okay, go to next step. If faulty circuit is found and repaired, go to step 10 .
6. Check for poor connections at BCM connector C2. If connections are okay, go to step 8 . If faulty connections are found and repaired, go to step 10 .
7. Check for poor connections at TCS connector. If connections are okay, go to step 9 . If faulty connections are found and repaired, go to step 10 .
8. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to step 10 .
9. Replace TCS switch. After repairs, go to next step.
10. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2 .

The following conditions may cause an intermittent

1. Intermittent short to ground in Brown/White wire between BCM and TCS switch.
2. TCS switch sticking or internally shorted to ground.
3. TCS switch is pressed for longer than 60 seconds.

If Brown/White wire between BCM and TCS switch is shorted to ground, TCS will stay on or off at all times depending on which state it was in when malfunction occurred. If short to ground occurred when TCS was on, TCS will remain off at all times. If short to ground occurred when TCS was off, TCS will remain on at all times. BCM will retain this information even if ignition is turned off.

The ambient light sensor provides input to Body Control Module (BCM) to control Daytime Running Light (DRL) operation. BCM provides 5 volt reference signal on Yellow/Black wire and ground signal on Light Green/Black wire to ambient light sensor. When ambient light is high, BCM will receive high voltage from ambient light sensor through Light Green/Black wire. When ambient light is low, BCM will receive low voltage from ambient light sensor through Light Green/Black wire.

BCM monitors ambient light sensor voltage signal to determine if return voltage is within range. Conditions for DTC B2647 to set are an open in one of the ambient light sensor circuits or a short to ground in Yellow/Black wire. Either of these conditions must occur for a minimum of 2 seconds for DTC B2647 to set.

When DTC B2647 sets in BCM, DRLs will remain on at all times and no driver warning message will be displayed. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2647 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2647 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, select BCM INPUTS and monitor AMBIENT LIGHT SENSOR data. If scan tool displays 0.1-2.5 volts, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If scan tool does not display 0.1-2.5 volts, go to next step.
3. Turn ignition off. Disconnect ambient light sensor connector. Ambient light sensor is located on top of the instrument panel in the defroster grille. Turn ignition on. Monitor AMBIENT LIGHT SENSOR data on scan tool. If scan tool displays less than 0.1 volt, go to next step. If scan tool displays greater than 0.1 volt, go to step 9 .
4. Turn ignition off. Connect a 3-amp jumper wire between ambient light sensor connector terminals "A" (Yellow/Black wire) and "B" (Light Green/Black wire). Turn ignition on. Monitor AMBIENT LIGHT SENSOR data on scan tool. If scan tool displays greater than 3.5 volts, go to next step. If scan tool displays less than 3.5 volts, go to step 7 .
5. Remove fused jumper. Using DVOM, measure voltage between ambient light sensor connector terminals. If voltage is greater than 5 volts, go to next step. If voltage is less than 5 volts, go to step 10 .
6. Check for short to voltage in Yellow/Black wire between BCM and ambient light sensor. If circuit is okay, go to step 11 . If faulty circuit is found and repaired, go to step 14 .
7. Check for short to ground in Yellow/Black wire between BCM and ambient light sensor. If circuit is okay, go to next step. If faulty circuit is found and repaired, go to step 14 .
8. Check for short to ground in Light Green/Black wire between BCM and ambient light sensor. If circuit is okay, go to step 11 . If faulty circuit is found and repaired, go to step 14 .
9. Check for short to voltage in Light Green/Black wire between BCM and ambient light sensor. If circuit is okay, go to step 11 . If faulty circuit is found and repaired, go to step 14 .
10. Check for poor connections at ambient light sensor connector. If faulty connections are found and repaired, go to step 14 . If connections are okay, go to step 12 .
11. Check for poor connections at BCM connector C1. If faulty connections are found and repaired, go to step 14 . If connections are okay, go to step 13 .
12. Replace ambient light sensor. After repairs, go to step 14 .
13. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
14. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2 .

The following conditions may result in an intermittent condition

1. Intermittent short to ground in Yellow/Black wire.
2. Intermittent open in Light Green/Black wire.
3. Internal open or short in ambient light sensor.

The ambient light sensor provides input to Body Control Module (BCM) to control Daytime Running Light (DRL) operation. BCM provides 5 volt reference signal on Yellow/Black wire and ground signal on Light Green/Black wire to ambient light sensor. When ambient light is high, BCM will receive high voltage from ambient light sensor through Light Green/Black wire. When ambient light is low, BCM will receive low voltage from ambient light sensor through Light Green/Black wire.

BCM monitors ambient light sensor voltage signal to determine if return voltage is within range. DTC B2648 will set if a short to voltage in one of the ambient light sensor circuits exists for a minimum of 2 seconds.

When DTC B2648 sets in BCM, DRLs will remain on at all times and no driver warning message will be displayed. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC B2648 will also clear when conditions no longer exist, and Instrument Panel Cluster (IPC) or scan tool is used to clear codes.

Note. If DTC B2648 is a history code, problem may be intermittent. Wiggle wires while performing the following test.

1. If BCM diagnostic system check has been performed, go to next step. If BCM diagnostic system check has not been performed, go to «BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-diagnostic-system-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, select BCM INPUTS and monitor AMBIENT LIGHT SENSOR data on scan tool. If scan tool displays 0.1-2.5 volts, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If scan tool does not display 0.1-2.5 volts, go to next step.
3. Turn ignition off. Disconnect ambient light sensor connector. Ambient light sensor is located on top of the instrument panel in the defroster grille. Turn ignition on. Monitor AMBIENT LIGHT SENSOR data on scan tool. If scan tool displays less than 0.1 volt, go to next step. If scan tool displays greater than 0.1 volt, go to step 9 .
4. Turn ignition off. Connect a 3-amp jumper wire between ambient light sensor connector terminals "A" (Yellow/Black wire) and "B" (Light Green/Black wire). Turn ignition on. Monitor AMBIENT LIGHT SENSOR data. If scan tool displays greater than 3.5 volts, go to next step. If scan tool displays less than 3.5 volts, go to step 7 .
5. Remove fused jumper. Using DVOM, measure voltage between ambient light sensor connector terminals. If voltage is greater than 5 volts, go to next step. If voltage is less than 5 volts, go to step 10 .
6. Check for short to voltage in Yellow/Black wire between BCM and ambient light sensor. If circuit is okay, go to step 11 . If faulty circuit is found and repaired, go to step 14 .
7. Check for short to ground in Yellow/Black wire between BCM and ambient light sensor. If circuit is okay, go to next step. If faulty circuit is found and repaired, go to step 14 .
8. Check for short to ground in Light Green/Black wire between BCM and ambient light sensor. If circuit is okay, go to step 11 . If faulty circuit is found and repaired, go to step 14 .
9. Check for short to voltage in Light Green/Black wire between BCM and ambient light sensor. If circuit is okay, go to step 11 . If faulty circuit is found and repaired, go to step 14 .
10. Check for poor connections at ambient light sensor connector. If faulty connections are found and repaired, go to step 14 . If connections are okay, go to step 12 .
11. Check for poor connections at BCM connector C1. If faulty connections are found and repaired, go to step 14 . If connections are okay, go to step 13 .
12. Replace ambient light sensor. After repairs, go to step 14 .
13. Replace BCM and program. See «BODY CONTROL MODULE (BCM)»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__body-control-module-bcm) under REMOVAL & INSTALLATION. See «BCM PROGRAMMING/RPO CONFIGURATION»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) under PROGRAMMING. After repairs, go to next step.
14. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Clear DTCs. If DTC resets, go to step 2 .

The following conditions may result in an intermittent condition

1. Intermittent short to voltage in Yellow/Black wire.
2. Intermittent short to voltage in Light Green/Black wire.

Serial data circuit is used to communicate information between systems. Each system on the serial data line is assigned its own identification number, which is used to identify which module or system is communicating. Systems periodically send a State of Health (SOH) message to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set. Also, any system that cannot communicate properly will set the corresponding DTC.

DTC U1000 or U1255 will set when module or system does not associate an identification number with a SOH message within five seconds.

DTC U1000 or U1255 will change from current to history after current ignition cycle if fault no longer exists. DTC U1000 or U1255 can be cleared using Drivers Information Center (DIC) or scan tool.

1. If any DTCs between U1001-U1254 are set as history, these DTCs must be repaired first. Go to «DTC U1001-U1254: LOSS OF COMMUNICATION WITH XXX»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) . If no DTCs between U1001-U1254 are set as history, go to next step.
2. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, attempt to establish communication with all systems connected to data line (i.e., PCM, BCM, RFA). If scan tool communicates with all systems, go to step 13 . If scan tool does not communicate with any systems, go to next step.
3. Check for open or short to ground in battery supply and ignition supply voltage circuit for module or system not communicating. See POWER DISTRIBUTION article in WIRING DIAGRAMS. If circuits are okay, go to next step. If faulty circuit is found, repair as necessary and go to step 9 .
4. Turn ignition off. Check for open in ground circuit for module or system not communicating. See GROUND DISTRIBUTION article in WIRING DIAGRAMS. If circuits are okay, go to next step. If faulty circuit is found, repair as necessary and go to step 9 .
5. Disconnect star connectors No. 1 and No. 2. See «COMPONENT LOCATIONS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__component-locations) . Ensure bus bar is properly inserted. Check for poor connections. If connections are okay, go to next step. If faulty connection is found, repair as necessary and go to step 9 .
6. Check for open in serial data line for module or system not communicating. See DATA LINK CONNECTORS article in WIRING DIAGRAMS. If circuits are okay, go to next step. If faulty circuit is found, repair as necessary and go to step 9 .
7. Check for poor connections at battery supply, ignition supply, ground and serial data line terminals for module or system not communicating. If connections are okay, go to next step. If faulty connection is found, repair as necessary and go to step 9 .
8. Replace module not communicating. After repairs, go to step 11 .
9. Turn ignition on. Reconnect all disconnect components and/or connectors. Display DTCs for module or system not communicating. If no additional DTCs that do not begin with "U" are set, go to next step. If any DTCs that do not begin with "U" are set, go to diagnostic system check in appropriate article for module or system not communicating.
10. Use scan tool to clear all DTCs. Go to next step.
11. Display DTCs for module that set DTC U1000 or U1255. If no additional DTCs that do not begin with "U" are set, go to next step. If any DTCs that do not begin with "U" are set, go to diagnostic system check in appropriate article for module or system not communicating.
12. Use scan tool to clear all DTCs. Test is complete.
13. If no additional DTCs are set for module that has DTC U1000 or U1255 set as current, go to next step. If any additional DTCs are set for module that has DTC U1000 or U1255 set as current, go to diagnostic system check in appropriate article for module or system not communicating.
14. Turn ignition off. Ensure scan tool is connected to DLC. Turn ignition on. Clear all DTCs using scan tool. Turn ignition off for a minimum of 5 seconds. Turn ignition on. Check for DTCs. If DTCs U1000 or U1255 are set as current, go to next step. If DTCs U1000 or U1255 are not set as current, go to «DIAGNOSTIC AIDS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules) .
15. Replace module that set DTCs U1000 or U1255 as current. Recheck system operation.

When a malfunction (such as an open fuse to a module) occurs while modules are communicating, a lost communication DTC will set as current. When modules stop communicating (ignition OFF), current lost communication DTC will be cleared but history DTC will remain. When modules begin to communicate again, the module with open fuse will not be learned by other modules so DTC U1000 or U1255 will be set as current by other modules. If malfunction occurs when modules are not communicating, only DTC U1000 or U1255 will set.

Modules connected along class 2 serial data line monitor serial data communications during normal vehicle operation. Operating information and commands are exchanged between modules and operating systems. When a module receives a message from another system, that module records identification number of system which sent State Of Health (SOH) message. If SOH is not received, receiving module must use a default value for non-transmitting identification number. Once an identification number is learned by a module, it will monitor that system for its unique SOH message. Each system on the class 2 serial data line must send a SOH message every two seconds. When no message is detected from any system for five seconds, DTC U1XXX (XXX is equal to the three digit identification number) will set. See DTC ID NUMBER table to determine which system is not communicating. For example, if DTC U1016 is set, Powertrain Control Module (PCM) is not communicating.

Current DTC will clear when SOH message from the failed identification number is detected on class 2 serial data line or at the end of the current ignition cycle. History DTC can only be cleared using scan tool or Driver's Information Center (DIC).

DTC ID NUMBER

1. Check for open in battery supply voltage circuit to module or system identified as not communicating. See POWER DISTRIBUTION article in WIRING DIAGRAMS. If battery supply voltage is present, go to next step. If battery supply voltage is not present, repair as necessary and go to step 9 .
2. Check for open in ground circuit to module or system identified as not communicating. See GROUND DISTRIBUTION article in WIRING DIAGRAMS. If ground circuit is okay, go to next step. If ground circuit is open, repair as necessary and go to step 9 .
3. Disconnect both star connectors. See «COMPONENT LOCATIONS»(/chevrolet/corvette/c5-1997-2004/remont/body-cab-control-systems/#body-control-modules__component-locations) . Check for poor connections. If connections are okay, go to next step. If poor connections are found, go to step 7 .
4. Check for open in serial data line between star connectors and module or system identified as not communicating. See DATA LINK CONNECTORS article in WIRING DIAGRAMS. If serial data line is okay, go to next step. If faulty serial data line is found, repair as necessary and go to step 7 .
5. Check for poor connections at battery supply, ground and serial data line terminals for module or system identified as not communicating. If connections are okay, go to next step. If faulty connections are found, repair as necessary and go to step 7 .
6. Replace module not communicating. After repairs, go to step 9 .
7. Reconnect all disconnect components and/or connectors. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Display DTCs for module or system identified as not communicating. If scan tool does not display any DTCs, go to next step. If scan tool displays any DTCs set that do not begin with "U", go to appropriate article for diagnostic and repair procedures for module or system identified as not communicating.
8. Use scan tool to clear all DTCs. After repairs, go to next step.
9. Display DTCs for module or system identified as not communicating. If scan tool does not display any DTCs, go to next step. If scan tool displays any DTCs set that do not begin with "U", go to appropriate article for diagnostic and repair procedures for module or system identified as not communicating.
10. Use scan tool to clear DTCs. Continue diagnosing and clearing DTCs until all modules or systems with stored DTCs are repaired.

The following conditions may cause a "U" code to set

1. Intermittent open or short in serial data line.
2. Intermittent open between the inoperative module and a star connector.
3. Poor connection at inoperative module or star connector.
4. Intermittent open in star connector.
5. Improperly powered module or system.

Serial data circuit is used to communicate information between systems. Each system on the serial data line is assigned its own recognition code, which is used to identify which system is communicating. Systems periodically send a State of Health (SOH) message to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set. Also, any system that cannot communicate properly will set the corresponding DTC.

When module detects no messages and a low voltage on class 2 serial data line for approximately three seconds, U1300 will set. Setting of all other class 2 serial communication DTCs will be disabled.

If conditions for malfunction no longer exist, DTC U1300 requires an ignition cycle to change from current to history. History DTC U1300 is cleared using Drivers Information Center (DIC) or scan tool.

DTC U1300 cannot be retrieved as current. If DTC U1300 is set, test class 2 serial data line. See SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SELF-DIAGNOSTIC SYSTEM. An intermittent condition can be caused by short to ground on class 2 serial data line.

Serial data circuit is used to communicate information between systems. Each system on the serial data line is assigned its own recognition code, which is used to identify which system is communicating. Systems periodically send a State of Health (SOH) message to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set. Also, any system that cannot communicate properly will set the corresponding DTC.

When module detects no messages and high voltage on the class 2 serial data link for approximately three seconds, U1301 will set. Setting of all other class 2 serial communication DTCs will be disabled.

If conditions for malfunction no longer exist, DTC U1301 requires an ignition cycle to change from current to history. DTC U1301 can be cleared using Instrument Panel Cluster (IPC) or scan tool.

DTC U1301 cannot be retrieved as current. If DTC U1301 is set, test class 2 serial data line. See SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SELF-DIAGNOSTIC SYSTEM. An intermittent condition can be caused by short to voltage on the class 2 serial data line.

BODY CONTROL MODULE (BCM)

Removal

Turn ignition off. Disconnect negative battery cable. Disengage upper latches of floor board panel. Open floor board panel, and lift up to remove floor board panel from bracket. To release BCM from bracket, pull up on BCM lower mounting tab. Lift BCM out of slots in bracket to release upper mounting tabs. (Scheme 9) Disconnect electrical connectors. Remove BCM.

Installation

Ensure ignition is off. Reconnect harness connectors. Position upper mounting tabs of BCM into slots in bracket. Push lower mounting tab into bracket, and snap BCM into place. Reinstall floor board panel. Reconnect negative battery cable. If a new BCM is being installed, reprogram BCM. See BCM PROGRAMMING/RPO CONFIGURATION under PROGRAMMING.

Scheme 9

FOGLIGHT/REAR HATCH SWITCH

Carefully pry the lower edge of the foglight/rear hatch switch to release locking tab. (Scheme 10) Disconnect electrical connectors and remove switch. To install, reverse removal procedure.

Scheme 10

Body Control Module Wiring Diagram (Corvette). Scheme 11

See also:
• STEERING COLUMN SWITCHES - CORVETTE
• POWER HATCH & FUEL DOOR RELEASE - CORVETTE
• ANTI-THEFT SYSTEMS - CORVETTE
• ANALOG INSTRUMENT PANELS - CORVETTE
• WIRING DIAGRAMS
• B2408
• SCAN TOOL DOES NOT POWER UP
• DIAGNOSTIC AIDS
• COMPONENT LOCATIONS
• BODY CONTROL MODULE DIAGNOSTIC SYSTEM CHECK
• BODY CONTROL MODULE (BCM)
• FOGLIGHT/REAR HATCH SWITCH