DESCRIPTION & OPERATION
| WARNING | Deactivate air bag system before performing any service operation. See appropriate AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy. |
Instrument Panel Cluster (IPC) consists of either a digital cluster or an analog cluster. (Scheme 1)or (Scheme 2). IPC has capability to diagnose malfunctions in various sensors, input switches, components and systems. When IPC or other microprocessor-controlled module detects a malfunction, it may turn on an IPC indicator or request/display a message to Driver Information Center (DIC) to alert driver that a malfunction has occurred. Some indicator lights and IPC messages have dual controls. See WARNING MESSAGES.
IPC contains 2 microprocessors as part of the instrument panel assembly. IPC can recognize operational malfunctions, alert driver through indicators or Driver Information Center (DIC) messages, and store DTCs which identify malfunction areas.
Scheme 1
Scheme 2
WARNING MESSAGES
Note. Not all messages apply to every vehicle.
Battery Not Charging (7)
When the PCM detects vehicle is not charging the battery. PCM sends a class 2 serial data message to IPC requesting this message be displayed.
Battery Saver Active (27)
When the DIM detects that the vehicle is in the battery saver mode. The DIM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Battery Voltage High (8)
When the PCM detects that the vehicle is over charging the battery, voltage is greater than 15.5 volts. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Battery Voltage Low (6)
When the PCM detects that the vehicle's battery voltage is less than 10 volts. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Change Brake Pads (125)
When the EBTCM does not detect a ground condition on the brake wear system circuit. The EBTCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Change Engine Oil (82)
When the PCM detects that the engine oil should be replaced. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Change Trans Fluid (47)
When the PCM detects that the transaxle fluid should be replaced. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Check Brake Fluid (37)
The IPC supplies ignition voltage to the brake fluid level switch via circuit 333 (PPL). The IPC monitors this circuit at connector C2 terminal B4, if the brake fluid level drops low enough the switch closes and circuit 333 (PPL) is grounded via circuit 151 (BLK/WHT). The IPC detects this ground condition and if the circuit remains grounded for at least one second, the IPC displays this message, sends a class 2 serial data message to the EBTCM, and illuminates the BRAKE indicator.
Check Coolant Level (2)
The IPC supplies ignition voltage to the coolant level switch via circuit 1478 (LT GRN). The IPC monitors this circuit at connector C2 terminal B3, if the coolant fluid level drops low enough the switch closes and circuit 1478 (LT GRN) is grounded via circuit 150 (BLK). When the IPC detects this ground condition and the circuit remains grounded for at least thirty (30) seconds, the IPC displays this message and sends a class 2 serial data message to the PCM.
Check Fuel Gage (50)
When the IPC detects that the fuel tank contains less than 15.2 liters (4 gallons). When this message is displayed the IPC sends a class 2 message requesting the radio to activate single chime.
Check Gas Cap (61)
When the PCM detects that a large vapor leak in the fuel system, i.e. a missing or loose gas cap. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Check Oil Level (36)
When the PCM does not detect a ground condition on circuit 1174 (BRN) for approximately thirty (30) minutes and the ignition switch is in ON with the engine not running. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Check Washer Fluid (25)
The IPC supplies ignition voltage to the windshield washer fluid level switch via circuit 99 (BLK/WHT). The IPC monitors this circuit at connector C2 terminal B5, if the windshield washer fluid level drops low enough the switch closes and circuit 99 (BLK/WHT) is grounded via circuit 1250 (BLK). The IPC detects this ground condition and if the circuit remains grounded for at least fifteen seconds, the IPC displays this message
Driver Door Ajar (140)
The LH Front Door Module (LFDM) supplies ignition voltage to the LH front door jamb switch via circuit 745 (BLK/WHT). The LFDM monitors this circuit at connector C2 terminal B, if the LH front door is ajar/open the switch closes and circuit 745 (BLK/WHT) is grounded via circuit 351 (BLK/WHT). The LFDM detects this ground condition and sends a class 2 serial data message to the IPC requesting that this message is displayed. If the vehicle speed is greater than 4.8 km/h (3 mph) the IPC displays the message and request the radio via a class 2 message to activate a multiple medium chime.
Driver No. X (1 or 2)
When the RFA module detects the transmitter (driver 1 or driver 2) used to unlock the vehicle. The RFA module sends a class 2 serial data message to the IPC requesting that the appropriate message is displayed.
Engine Coolant Hot Idle Engine (44)
When the PCM detects that an overheated engine condition exists and the RPM is below 1000. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Engine Hot AC Off (16)
When the PCM detects that an overheated engine condition exists. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Engine Misfire Ease Off Gas Pedal (57)
When the PCM detects that an engine misfire condition exists. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed. When this message is displayed a multiple medium chime is activated.
Engine Overheated Stop Engine (42)
When the PCM detects that a severe overheated engine condition exists. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed. When this message is displayed a multiple medium chime is activated.
Fuel Level Low (11)
The IPC displays this message if the fuel level drops below 15 liters (4 gallons). When this message is displayed a single low chime is activated.
Headlamps Suggested (62)
When the DIM detects that the ambient light sensor senses a dark condition, the gear selector is not in PARK, the twilight sentinel switch is OFF, and the headlamps or fog lamps are off. The DIM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Ice Possible (63)
When the IPM detects that the outside temperature sensor determines that the outside temperature is below 0°C (36°F). The IPM sends a class 2 serial data message to the IPC requesting that this message is displayed. When this message is displayed a single low chime is activated.
Left Rear Door Ajar (142)
The LH Rear Door Module (LRDM) supplies ignition voltage to the LH rear door jamb switch via circuit 747 (LT BLU/BLK). The LRDM monitors this circuit at connector C2 terminal B, if the LH rear door is ajar/open the switch closes and circuit 747 (LT BLU/BLK) is grounded via circuit 551 (BLK/WHT). The LRDM detects this ground condition and sends a door ajar/open status (serial data) message via the Simple Data Interface (SBI) to the LFDM. The LFDM detects this door open/ajar message and sends a class 2 serial data message to the IPC requesting that this message is displayed. If the vehicle speed is greater than 4.8 km/h (3 mph) the IPC displays the message and request the radio via a class 2 message to activate a multiple medium chime.
Oil Pressure Low Stop Engine (35)
When the PCM detects that a severe low engine oil condition exists. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Passenger Door Ajar (141)
The RH Front Door Module (RFDM) supplies ignition voltage to the RH front door jamb switch via circuit 746 (BLK/WHT). The RFDM monitors this circuit at connector C2 terminal B, if the RH front door is ajar/open the switch closes and circuit 746 (BLK/WHT) is grounded via circuit 451 (BLK/WHT). The RFDM detects this ground condition and sends a door ajar/open status (serial data) message via the Simple Data Interface (SBI) to the LFDM. The LFDM detects this door open/ajar message and sends a class 2 serial data message to the IPC requesting that this message is displayed. If the vehicle speed is greater than 4.8 km/h (3 mph) the IPC displays the message and request the radio via a class 2 message to activate a multiple medium chime.
Right Rear Door Ajar (143)
The RH Rear Door Module (RRDM) supplies ignition voltage to the RH rear door jamb switch via circuit 747 (BLK/WHT). The RRDM monitors this circuit at connector C2 terminal B, if the RH rear door is ajar/open the switch closes and circuit 747 (LT BLU/BLK) is grounded via circuit 451 (BLK/WHT). The RRDM detects this ground condition and sends a door ajar/open status (serial data) message via the Simple Data Interface (SBI) to the LFDM. The LFDM detects this door open/ajar message and sends a class 2 serial data message to the IPC requesting that this message is displayed. If the vehicle speed is greater than 4.8 km/h (3 mph) the IPC displays the message and request the radio via a class 2 message to activate a multiple medium chime.
Service A/C System (14)
When the Integration Panel Module (IPM) detects that a A/C system malfunction exists. The IPM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Air Bag (83)
When the SDM detects that a inflatable restraints system malfunction exists. The SDM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Charging Sys (102)
When the PCM or DIM detects that a charging system malfunction exists. The respective module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Electrical Sys (106)
When the PCM detects that a electrical system malfunction desist. The respective module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Fuel System (101)
When the PCM detects that a fuel system malfunction desist. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Idle Control 1(07)
When the PCM detects that a idle control system malfunction desist. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Stability Sys (54)
When the RTD module detects a suspension system malfunction. The RTD module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Steering Sys (127)
When the ABS module detects a steering system malfunction. The ABS module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Suspension Sys (84)
When the RTD module detects a suspension steering system malfunction. The RTD module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Theft System (34)
When the VTD module detects a PASS-Key(R) III system malfunction. The VTD module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Service Transmission
When the PCM detects that a transmission malfunction desist. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
SERVICE VEHICLE SOON (3)
When the PCM detects that a non--emissions related malfunction desist. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Speed Limited To 90 Mph (113)
When the RTD detects that a suspension related malfunction desist and the PCM has received a class 2 message to limit vehicle speed. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Stability Sys Engaged (55)
When the RTD module has detected that the vehicle is just starting to spin. The RTD module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Starting Disabled Remove Key (33)
When the VTD module has detected an invalid ignition key being used to start the vehicle, the vehicle theft deterrent system is activated. The VTD module sends a class 2 serial data message to the IPC requesting that this message is displayed.
Theft Attempted (40)
When the Rear Integration Module (RIM) has detected a forced entry into the vehicle, activating the CTD system alarm, the RIM saves the event to memory. When the RIM detects a ignition switch ON state, the RIM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Top Speed Fuel Cut-Off (111)
When the PCM detects that the vehicle has reached its calibrated maximum speed. The PCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Traction Engaged (91)
When the EBTCM is limiting wheel spin, the EBTCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Traction Off (89)
When the EBTCM detects that the traction control switch is in the OFF position. The EBTCM sends a class 2 serial data message to the IPC requesting that this message is displayed.
Traction Ready (90)
When the EBTCM detects that the traction control switch was turned from the OFF to ON position. The EBTCM sends a class 2 serial data message to the IPC requesting that this message is displayed. This message cancels after five seconds.
Traction Suspended (56)
When the EBTCM suspended traction control operation, because the brakes have overheated. The EBTCM sends a class 2 serial data message to the IPC requesting that this message is displayed. This message cancels after five seconds. This message does not indicate a malfunction with the traction control system, after a few minutes the traction control system should be active.
Trans Hot Idle Engine (112)
The IPC displays this message when a class 2 serial data request is received from the PCM. This message indicates either the transaxle has been hotter than 144°C (291°F) for more than 32 seconds or hotter than 130°C (266°F) for than 15 minutes. The transaxle must be less than 120°C (248°F) for more than 5 seconds to clear this message.
Trunk Open 24
The IPC supplies ignition voltage to the rear compartment lid release switch via circuit 744 (RED/BLK). When the ignition switch is ON, the IPC monitors circuit 744 (RED/BLK) at connector C2 terminal B6. When the rear compartment lid is open the switch closes and circuit 744 (RED/BLK) is connected to grounded via circuit 850 (BLK). The IPC detects this ground condition for at least one second, the IPC displays this message.
Turn Signal On (20)
The IPC monitors circuit 14 (DK BLU) at connector C1 terminal B12 and circuit 15 (LT BLU) at connector C1 terminal B11. When the LH or RH turn signal switch is on the IPC detects a voltage condition. If the circuit remains active for at least 1.6 km ( 1 mile), the IPC displays this message. Also, the IPC sends a class 2 message requesting the radio to activate a multiple chime.
COMPONENT LOCATIONS
| Component | Location |
|---|---|
| Brake Fluid Level Switch | In Master Cylinder Reservoir |
| Climate Control Panel (CCP) | Center Of Instrument Panel, Near Radio |
| Coolant Level Switch | In Bottom Of Coolant Reservoir |
| Door Jamb Switch | Rear Of Door, On Door Latch Assembly |
| Driver Information Center (DIC) Switch | Center Of Instrument Panel, Near Radio |
| Electronic Brake/Traction Control Module (EBTCM) | Left Front Corner Of Engine Compartment, On Brake Pressure Modulator Valve |
| Generator | Right Front Corner Of Engine Compartment, Near Battery |
| Headlight Switch | Left Side Of Instrument Panel, Left Of Steering Column |
| Key-In-Ignition Switch | In Steering Column, Near Steering Column Lock Cylinder |
| Oil Level Switch | In Engine Oil Pan, Near A/C Compressor |
| Oil Pressure Switch | On Center Of Engine, Near Battery |
| Parking Brake Switch | Under Left Side Of Instrument Pedal, On Parking Brake Pedal |
| Platform Zone Module (PZM) (1) | Front Of Trunk Compartment, On Electronics Bay |
| Powertrain Control Module (PCM) | Left Front Corner Of Engine Compartment, Under Air Cleaner Housing |
| Trunk Compartment Fuse Block | Front Of Trunk Compartment, On Electronics Bay |
| Trunk Pull-Down Motor | Center Rear Of Trunk, Near Lid Latch |
| Windshield Washer Fluid Level Switch | Left Front Corner Of Engine Compartment, Behind Front Fascia |
| (1) Platform Zone Module (PZM) may also be referred to as Body Control Module (BCM). For more information, see BODY CONTROL MODULES - DEVILLE & ELDORADO article. | |
| (1) | Platform Zone Module (PZM) may also be referred to as Body Control Module (BCM). For more information, see BODY CONTROL MODULES - DEVILLE & ELDORADO article. |
COMPONENT LOCATIONS
HANDLING PRECAUTIONS
| CAUTION | When handling Electrostatic Discharge (ESD) sensitive electronic parts, specific care should be given to avoid damaging components. Specific care is as follows: Discharge personal static electricity by momentarily touching metal grounding point on vehicle before coming in contact with electronic components. NEVER touch terminals on components or connectors with fingers or metal tools. When disconnecting connectors, NEVER let metal tool contact any exposed terminal. NEVER jumper, ground or use test meter probes on components or connectors unless specified in diagnostic procedures. Always connect ground lead first. DO NOT remove solid-state components from protective packaging until ready for installation. Touch packaging to ground before opening. DO NOT bump or drop component. DO NOT lay component on metal work bench or electrically operated components (such as radio, TV or oscilloscope). |
CHANGING IPC OVERRIDE DISPLAY
| CAUTION | If any override values are changed without following the correct procedure, DTC B1557 may set. This DTC cannot be cleared, and IPC must be replaced. If OFF button is pressed and IPC displays IPC CLEAR CODE message, exit vehicle diagnostic system and start over. This will reset original override values and prevent DTC B1557 from setting. |
Note. When Electronically Erasable Programmable Read Only Memory (EEPROM) option Byte No. 2 (override option B) is set for Saudi Arabia (4), speedometer will flash if vehicle speed is greater than 75 MPH (121 KM/H). When vehicle is traveling above this speed, display will continue to flash, but actual vehicle speed will be displayed. When Electronically Erasable Programmable Read Only Memory (EEPROM) option Byte No. 2 (override option B) is set for Japanese (8), speedometer will not display greater than 112 MPH (180 KM/H). When vehicle is traveling above this speed, display will flash 112 MPH (180 KM/H).
- To change override value, add value of new feature to displayed override value. See «OVERRIDE DISPLAY VALUES»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. To increase override value displayed in trip odometer, press warmer (Red bar) button (digital cluster) or passenger warmer (up arrow) button (analog cluster). To decrease override value displayed in trip odometer, press cooler (Blue bar) button (digital cluster) or passenger cooler (down arrow) button (analog cluster).
- To permanently store new override value, perform the following for about 5 seconds until new override value flashes once: On digital cluster, press and hold front defrost (symbol) and AUTO/ECON buttons. On analog cluster, press and hold front defrost (symbol) and A/C buttons.
| Application | Display | |
|---|---|---|
| Option Byte "A" | ||
| Universal Theft Deterrent Enable | 8 | |
| Memory/Personalization Present | 4 | |
| Always Set | 1 | |
| Option Byte "B" (Export Country) | ||
| European Economic Community Mode | 16 | |
| Japanese Mode | 8 | |
| Saudi Arabian Mode | 4 | |
| Canadian Mode | 2 | |
| Norway/Sweden Mode | 1 | |
| Option Byte "C" | ||
| RSS Installed | 128 | |
| Premium Unleaded Fuel Display Disable | 64 | |
| Always Set | 32 | |
| Cellular Telephone Present | 16 | |
| Brake To Shift Interlock Message Suppression | 4 | |
| Options Not Set Message Suppression | 2 | |
| Low Fuel Level Message Suppression | 1 | |
| Option Byte "D" (HVAC Options) | ||
| Afterblow Enabled | 128 | |
| Dual Zone Present | 8 | |
| Option Byte "E" (Driver's Message Center Display Options) | ||
| Coolant Temperature Message | 64 | |
| Battery Volts Message | 32 | |
| Engine RPM Message | 16 | |
| AVG MPH Message | 8 | |
| MPH Message | 4 | |
| Fuel Used Message | 2 | |
| INST MPG Message | 1 | |
| (1) Current override values are displayed in trip odometer display. | ||
| (1) | Current override values are displayed in trip odometer display. |
OVERRIDE DISPLAY VALUES (1)
REPROGRAMMING IPC
Note. This theft-deterrent relearn procedure must be performed when IPC has been replaced so that new IPC can learn vehicle's key code value.
Note. Vehicle battery must maintain a minimum of 10.5 volts. If battery is not fully charged or is weak, connect a battery charger to maintain battery voltage. DO NOT set battery charger in 12-volt boost mode, as this will prevent this procedure from working.
Turn ignition switch to RUN position. Wait a minimum of 10 minutes. Cycle ignition switch from RUN to OFF to RUN position. Wait a minimum of 10 minutes. Cycle ignition switch from RUN to OFF to RUN position. Wait a minimum of 10 minutes. Turn ignition switch to OFF position. Recheck system operation.
SELF-DIAGNOSTIC SYSTEM
IPC is equipped with an extensive diagnostic system which is capable of detecting and compensating for malfunctions and alerting the driver of a malfunction.
Diagnostic Trouble Codes (DTCs)
Diagnostic Trouble Codes (DTCs) indicate that IPC has detected a malfunction in a circuit or other system. IPC is programmed with routines for internal checks that it follows only when prescribed test conditions exist. When these conditions exist, IPC checks certain circuits or systems for a malfunction. These checks are called failure conditions. When a failure condition is present, a DTC is set. Some DTCs alert the driver through a Driver Information Center (DIC) message. Other DTCs do not trigger a driver warning. DTCs are stored in the IPC EEPROM or other modules and are retained even if battery is disconnected.
Current DTC
When IPC determines that test conditions and failure conditions for a particular DTC are true, it sets that DTC as current. All DTCs remain current until the next time IPC finds test conditions are true and failure conditions are false. A few DTCs remain current until next ignition cycle or until failure conditions are false several times.
History DTC
After a DTC has been set, IPC continues to monitor for test and failure conditions. For most DTCs, if test conditions are true and failure conditions are false, DTC is changed to history. Some DTCs require test conditions to be true and failure conditions false several times or require an ignition cycle to change from current to history. If there are no current DTCs for 50 ignition cycles, all history DTCs will be cleared.
RETRIEVING & CLEARING DTCS
Note. Diagnostic Trouble Codes (DTCs) for other systems can also be retrieved during this procedure. Only information related to IPC diagnosis is covered in this article.
Retrieving DTCs Using Scan Tool
Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Scan tool can read IPC inputs and outputs. See scan tool manufacturer's instructions
Retrieving DTCs Without Scan Tool
- Turn ignition switch to ON position. On analog IPC, press OFF and passenger warmer (up arrow) buttons on Climate Control Panel (CCP) until all segments of display are illuminated. On digital IPC, press OFF and warmer (Red bar) buttons on Climate Control Center (CCC) until all segments of display are illuminated.
- On all models, Driver Information Center (DIC) will display all set DTCs (current or history). DTCs will be displayed in the following order: PCM, IPC, ACM, SDM, TCS, RSS, PZM, IRC, RFA, CCP, MSM, MMM and PHN. See «ABBREVIATIONS & DEFINITIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. Pressing FAN DOWN button will by-pass DTC display.
Clearing DTCs
IPC CLEAR CODES option can be used to clear stored IPC DTCs. When selected, IPC CLEAR CODES option immediately erases all DTCs stored to that point and DIC displays IPC CODES CLEAR. Once a malfunction has been corrected, clear DTCs so future service is not complicated by history codes for repaired problems. After DTC has been cleared, it is necessary to verify proper system operation. To ensure system is operating properly, duplicate conditions under which DTC was originally set and recheck for codes.
| Abbreviation | Definition |
|---|---|
| ACM | Air Control Module |
| CCC (1) | Climate Control Center |
| CCP (2) | Climate Control Panel |
| IPC | Instrument Panel Cluster |
| IRC | Integrated Radio Chassis |
| MMM (3) | Memory Mirror Module |
| MSM (3) | Memory Seat Module |
| PCM | Powertrain Control Module |
| PZM | (4) Platform Zone Module |
| RFA | Remote Function Actuator |
| RSS (3) | Road Sensing Suspension |
| SDM | Sensing & Diagnostic Module |
| TCS | Traction Control System |
| PHN (3) | Telephone |
| (1) Digital instrument panel. (2) Analog instrument panel. (3) Vehicle may not be equipped with these options. (4) Platform Zone Module (PZM) may also be referred to as Body Control Module. | |
| (1) | Digital instrument panel. |
| (2) | Analog instrument panel. |
| (3) | Vehicle may not be equipped with these options. |
| (4) | Platform Zone Module (PZM) may also be referred to as Body Control Module. |
ABBREVIATIONS & DEFINITIONS
IPC DTC DEFINITIONS
Note. Diagnostic trouble code tests are written specifically for use with GM Tech I or Tech II scan tools. Generic scan tool can be used, but may have limited functions.
| DTC No. | Circuit Affected |
|---|---|
| B1552 | Loss of Keep Alive Memory (KAM) |
| B1556 | IPC EEPROM Odometer Error |
| B1557 | EEPROM Calibration Error |
| B1910 | Generator "L" Terminal Open Circuit |
| B1911 | Generator "L" Terminal Malfunction |
| B1981 | Source Voltage Low (Engine Running) |
| B1982 | Source Voltage High |
| B1983 | Source Voltage Low |
| B2419 | Twilight Sentinel Photo Sensor Malfunction |
| B2510 | Steering Wheel Controls HVAC Key Stuck |
| B2511 | Steering Wheel Controls Convenience Key Stuck |
| B2515 | Steering Wheel Controls Illegal Resistance Value |
| B2710 | PASS-Key(R) II Open/Short Key Pellet |
| B2711 | PASS-Key(R) II Open/Short Key Pellet |
| B2750 | PASS-Key(R) II Data Communication Malfunction |
| B2780 | PASS-Key(R) II Wrong Resistor Value Before Good |
| B2781 | PASS-Key(R) II Wrong Resistor Value After Good |
| B2782 | PASS-Key(R) II Pellet Value Not Programmed |
| B2783 | PASS-Key(R) II Code/Password Corrupted |
| C1210 | Brake Fluid Level Switch Open |
| U1016 | Loss Of Serial Communications - PCM |
| U1040 | Loss Of Serial Communications - ABS |
| U1064 | Loss Of Serial Communications - PZM |
| U1088 | Loss Of Serial Communications - SDM |
| U1144 | Loss Of Serial Communications - PHN |
| U1152 | Loss Of Serial Communications - ACM |
| U1153 | Loss Of Serial Communications - CCP |
| U1255 | Class 2 Initialization Error |
IPC DTC DEFINITIONS
DIAGNOSTIC TESTS
Note. Before performing any IPC testing or diagnostic procedures, ensure that all aftermarket electrical equipment is disconnected from vehicle. If any circuits have been spliced into for installation of aftermarket equipment, ensure circuit is operating properly.
Note. For component locations, see COMPONENT LOCATIONS . For wiring and connector terminal identification, see WIRING DIAGRAMS .
IPC DIAGNOSTIC SYSTEM CHECK
- Turn ignition switch to RUN position. Wait one minute. If SERVICE ENGINE SOON indicator is still illuminated, go to appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If SERVICE ENGINE SOON indicator is not illuminated, go to next step.
- Turn ignition switch to OFF position. Connect scan tool. Turn ignition switch to RUN position. Using scan tool, request IPC DTC display. If scan tool receives data, go to next step. If scan tool does not receive data, locate and repair problem in Platform Zone Module (PZM) system. See BODY CONTROL MODULES - DEVILLE & ELDORADO article.
- If any current DTC exists, go to appropriate DTC test. If no current DTCs exist, go to next step.
- Clear any history DTCs. See «RETRIEVING & CLEARING DTCS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__retrieving-clearing-dtcs) under SELF-DIAGNOSTIC SYSTEM. Test drive vehicle. Recheck system.
Description
DTC B1552 indicates that battery-backed or Keep Alive Memory (KAM) has been reset. This occurs when power or ground is removed from IPC (such as disconnecting vehicle battery).
DTC B1552 will set when there is a short in class 2 serial data line and PZM attempts to activate low power mode (about 20 minutes after ignition switch is turned to OFF position). If PZM DTC B1552 is also set, a battery disconnection probably occurred.
When DTC B1552 is set, IPC KAM data (trip odometer and timer) is reset to initial values. Average fuel economy, fuel used and average MPH will reset to zero. If battery is disconnected, climate control will default to automatic HVAC mode and automatic fan mode, and display a set temperature of 75°F. If only IPC was disconnected, climate control should return to previous settings when ignition switch is turned to ON position.
Testing
- If B1552 sets without an apparent battery disconnect, check for PZM DTCs B1972 or B1973. If PZM DTC B1972 or B1973 do not exist, go to next step. If PZM DTC B1972 or B1973 exist, go to appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
- Check for poor terminal contact at IPC Blue 24-pin connector C1, terminals A1 (Orange wire), B1 (Orange wire), A12 (Black/White wire) and B12 (Black/White wire). (Scheme 3) Repair as necessary. If no problem is found, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Clear codes and check system operation.
Scheme 3
DTC B1556 will set when odometer portion of IPC Electronically Erasable Programmable Read Only Message (EEPROM), which stores vehicle mileage, has an unrecoverable error and is no longer accurate. When DTC B1556 is set, season odometer will display ERROR.
Replace IPC. See INSTRUMENT PANEL CLUSTER (IPC) under REMOVAL & INSTALLATION. Obtain approximate mileage, and contact an authorized Delco service center for transfer of information from failed IPC to replacement IPC.
DTC B1557 will set when IPC Electronically Erasable Programmable Read Only Message (EEPROM) microprocessor (which stores calibrations for analog gauge, manufacturing information, vehicle option information and VIN) has an unrecoverable error.
When DTC B1557 is set, IPC will use default calibrations, SERVICE VEHICLE SOON indicator will illuminate, driver message center will display OPTIONS NOT SET, manufacturing data and VIN will change to zero, and override display information will set as specified. See OVERRIDE DISPLAY INFORMATION table.
| Application | Display | |
|---|---|---|
| Option Byte "A" | ||
| Universal Theft Deterrent Enable | OFF | |
| Memory/Personalization Present | OFF | |
| Option Byte "B" | ||
| European Economic Community Mode | OFF | |
| Japanese Mode | OFF | |
| Saudi Arabian Mode | OFF | |
| Canadian Mode | OFF | |
| Norway/Sweden Mode | OFF | |
| Option Byte "C" | ||
| Premium Unleaded Fuel Display Disable | OFF | |
| Cellular Telephone Present | OFF | |
| Brake To Shift Interlock Message Suppression | OFF | |
| Options Not Set Message Suppression | ON | |
| Low Fuel Level Message Suppression | OFF | |
| RSS Present | OFF | |
| Option Byte "D" | ||
| Afterblow Option | OFF | |
| Dual Zone Present | OFF | |
| Option Byte "E" | ||
| Coolant Temperature Message Suppression | OFF | |
| Battery Volts Message Suppression | OFF | |
| Engine RPM Message Suppression | OFF | |
| AVG MPH Message Suppression | OFF | |
| MPH Message Suppression | OFF | |
| Fuel Used Message Suppression | OFF | |
| INST MPG Message Suppression | OFF | |
OVERRIDE DISPLAY INFORMATION
Replace IPC. See INSTRUMENT PANEL CLUSTER (IPC) under REMOVAL & INSTALLATION. Obtain approximate mileage, and contact an authorized Delco service center for transfer of information from failed IPC to replacement IPC.
Generator grounds circuit No. 225 (Red wire) when ignition switch is in RUN position and engine speed is less than 400 RPM. DTC B1910 will set when IPC determines that engine speed is less than 400 RPM and senses a high voltage (open) in generator "L" terminal feedback circuit. This circuit will only be tested when ignition switch is in RUN position, engine speed is less than 400 RPM and vehicle diagnostic system is not activated.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Turn ignition switch to OFF position. Connect scan tool. Turn ignition switch to ON position. Using scan tool, check IPC data list input for ALT L TERMINAL. If scan tool does not display ON, go to next step. If scan tool displays ON, go to step 5.
- Turn ignition switch to OFF position. Disconnect IPC Blue 24-pin connector C1. Disconnect generator. Using DVOM, check resistance of Red wire between IPC connector C1, terminal A9 and generator "L" terminal. (Scheme 3) If resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, repair open circuit in Red wire between IPC connector C1 and generator. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Reconnect IPC connector C1. Turn ignition switch to RUN position. Using DVOM, check voltage between generator connector "L" terminal (Red wire) and ground. If voltage is not greater than 10 volts, go to next step. If voltage is greater than 10 volts, locate and repair problem in charging system. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
DTC B1911 indicates a circuit malfunction is preventing generator from charging. DTC B1911 will set when IPC determines that circuit No. 225 (Red wire) is grounded by generator with ignition switch in RUN position and engine speed is greater than 600 RPM. This test is only performed when ignition switch is in RUN position, IPC measures engine speed greater than 600 RPM and vehicle diagnostics is not active. When DTC B1911 is set, IPC will display BATTERY NOT CHARGING message and battery indicator will illuminate.
Using DVOM, check for battery voltage at generator "L" terminal (Red wire) while engine is running. If battery voltage exists, check for intermittent short or open in Red wire between IPC connector C1 terminal A9 and generator. Also check for intermittent short or open in Gray wire between generator and PCM Blue 80-pin connector C1, terminal No. 54. Repair as necessary and recheck system operation. If circuits are okay, check for internal malfunction in generator. Repair as necessary and recheck system operation.
When IPC is awake, IPC continuously checks for battery voltage at connector C1, terminals A1 (Orange wire) and B1 (Orange wire). DTC B1981 will set when IPC measures engine speed greater than 1500 RPM, and voltage at IPC connector C1, terminals A1 and B1 is less than 10 volts for 2 seconds.
When DTC B1981 is set, driver message center on IPC will display BATTERY VOLTAGE LOW. If voltage drops below 9 volts, IPC turns off all unnecessary dimming VF display circuits.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- With engine running, use DVOM to check for voltage at both fuse test terminals of CLUSTER fuse (20-amp), located in trunk compartment fuse block. If reading is greater than 10 volts, go to next step. If reading is not greater than 10 volts, go to step 6.
- Connect scan tool. Using scan tool, check IPC data list value for BATTERY VOLTAGE. If scan tool displays greater than 10 volts, go to next step. If scan tool does not display greater than 10 volts, go to step 5.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Repair open in Orange wire between IPC Blue 24-pin connector C1 and trunk compartment fuse block. (Scheme 3) Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Check CLUSTER fuse. If fuse is open, replace fuse. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check). If fuse is okay, locate and repair problem in circuit between battery and trunk compartment fuse block. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
When IPC is awake, IPC continuously checks for battery voltage at connector C1, terminals A1 (Orange wire) and B1 (Orange wire). DTC B1982 will set when voltage at IPC connector C1, terminals A1 and B1 is more than 15.5 volts for 1200 milliseconds.
When DTC B1982 is set, driver message center on IPC will display BATTERY VOLTAGE HIGH. If DTC B1982 is a current code, no loss of class 2 serial data DTCs will be set.
Note. DTC B1982 may set if vehicle is connected to a battery charger set on fast or boost charge.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- With engine running, use DVOM to check for voltage at one fuse test terminal of CLUSTER fuse (20-amp), located in trunk compartment fuse block. If reading is not greater than 15.5 volts, go to next step. If reading is greater than 15.5 volts, locate and repair problem in charging system. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
When IPC is awake, IPC continuously checks for battery voltage at connector C1, terminals A1 (Orange wire) and B1 (Orange wire). DTC B1983 will set when voltage at IPC connector C1, terminals A1 and B1 is less than 9 volts for 1200 milliseconds. If DTC B1983 is a current code, no loss of class 2 serial data DTCs will be set.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- With engine running, use DVOM to check for voltage at both fuse test terminals of CLUSTER fuse (20-amp), located in trunk compartment fuse block. If reading is greater than 10 volts, go to next step. If reading is not greater than 10 volts, go to step 6 .
- Connect scan tool. Using scan tool, check IPC data list value for BATTERY VOLTAGE. If scan tool displays greater than 10 volts, go to next step. If scan tool does not display greater than 10 volts, go to step 5 .
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Repair open in Orange wire between IPC Blue 24-pin connector C1 and trunk compartment fuse block. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Check CLUSTER fuse. If fuse is open, replace fuse. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) . If fuse is okay, locate and repair problem in circuit between battery and trunk compartment fuse block. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
IPC monitors steering wheel control keys input at IPC connector C2, terminal B11 (Dark Blue wire). (Scheme 3) IPC interprets button commands, and sends appropriate message on class 2 serial data line. DTC B2510 will set when IPC determines that steering wheel touch control key for FAN UP (phone), FAN DOWN (recall), TEMP UP (send) or TEMP DOWN (end) is active for more than 12.5 seconds.
- Check for binding, sticking, or broken steering wheel touch controls. If steering wheel touch control keys are okay, clear DTC. Check operation of steering wheel controls. If DTC resets, replace steering wheel touch control keys.
- Each steering wheel control key has a unique counts value. To check counts, connect scan tool. Press each steering wheel control switch. See «STEERING WHEEL TOUCH CONTROL SPECIFICATIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. If count value is not as specified, repair or replace as necessary.
- Each steering wheel control key has a unique resistance. These resistance values can be measured by disconnecting Black 48-pin connector C202 (located under instrument panel near base of steering column). Using DVOM, check resistance between connector C202 terminals A1 (Dark Blue wire) and A4 (Orange wire) while operating steering wheel touch controls. See «STEERING WHEEL TOUCH CONTROL SPECIFICATIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. (Scheme 4) If resistance is not as specified, repair or replace as necessary.
| Function | Count Range | Resistance (Ohms) |
|---|---|---|
| Volume Up | 212-240 | 1270 |
| Volume Down | 181-202 | 1549-1579 |
| Select Up | 153-172 | 1893-1931 |
| Select Down | 126-145 | 2363-2411 |
| Phone/Temp Up | 90-117 | 3071-3133 |
| Phone/Temp Down | 73-91 | 4240-4324 |
| Send/Fan Up | 45-63 | 6586-6718 |
| End/Fan Down | 19-37 | 13,496-13,768 |
| No Key Pressed | 0-18 | Infinite |
STEERING WHEEL TOUCH CONTROL SPECIFICATIONS
Scheme 4
IPC monitors steering wheel control keys input at IPC connector C2, terminal B11 (Dark Blue wire). (Scheme 3) IPC interprets button commands, and sends appropriate message on class 2 serial data line. DTC B2511 will set when IPC determines that VOLUME UP, VOLUME DOWN, SELECT UP or SELECT DOWN is active for more than 5 seconds.
- Check for binding, sticking, or broken steering wheel touch controls. If steering wheel touch control keys are okay, clear DTC. Check operation of steering wheel controls. If DTC resets, replace steering wheel touch control keys.
- Each steering wheel control key has a unique counts value. Connect scan tool. Press each steering wheel control switch. See «STEERING WHEEL TOUCH CONTROL SPECIFICATIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. If count value is not as specified, repair or replace as necessary.
- Each steering wheel control key has a unique resistance. These resistance values can be measured by disconnecting Black 48-pin connector C202, located under instrument panel near base of steering column. Using DVOM, check resistance between connector C202 terminals A1 (Dark Blue wire) and A4 (Orange wire) while operating steering wheel touch controls. See «STEERING WHEEL TOUCH CONTROL SPECIFICATIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. (Scheme 4) If resistance is not as specified, repair or replace as necessary.
IPC monitors steering wheel control keys input at IPC connector C2, terminal B11 (Dark Blue wire). (Scheme 3) IPC interprets button commands, and sends appropriate message on class 2 serial data line. DTC B2515 will set when IPC receives a value that is not within resistance value range.
- Check for binding, sticking, or broken steering wheel touch controls. If steering wheel touch control keys are okay, clear DTC. Check operation of steering wheel controls. If DTC resets, replace steering wheel touch control keys.
- Check for open or short in Dark Blue wire between IPC Gray 24-pin connector C2, terminal B11 and Black 48-pin pin connector C202 (located under instrument panel, near base of steering column). (Scheme 3)and (Scheme 4). Repair as necessary.
- Each steering wheel control key has a unique counts value. To check value, connect scan tool. Press each steering wheel control switch. See «STEERING WHEEL TOUCH CONTROL SPECIFICATIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. If count value is not as specified, repair or replace as necessary.
- Each steering wheel control key has a unique resistance. These resistance values can be measured by disconnecting Black 48-pin connector C202. Using DVOM, check resistance between connector C202 terminals A1 (Dark Blue wire) and A4 (Orange wire) while operating steering wheel touch controls. See «STEERING WHEEL TOUCH CONTROL SPECIFICATIONS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) table. (Scheme 4) If resistance is not as specified, repair or replace as necessary.
When ignition key is inserted in ignition, resistance of key pellet is measured. Resistance is compared with resistance value stored in IPC memory. DTC B2710 will set when an open or zero resistance value is measured from key pellet prior to obtaining a valid resistance reading. DTC B2711 will set when an open or zero resistance value is measured from key pellet following a valid resistance reading. When DTC B2710 is set as current, IPC will display STARTING DISABLED, REMOVE IGNITION KEY message on driver's message center and prevent vehicle from starting. When DTC B2711 is set as current, IPC will display THEFT SYSTEM PROBLEM, CAR MAY NOT RESTART message on driver's message center and allow vehicle to continue to run.
Diagnostic Aids
Check for intermittent open, short or loose connections in circuit No. 1073 (White/Black wire) or No. 1074 (Purple/White wire) between IPC connector C1 and connector C202.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Insert key into ignition switch. Disconnect Black 48-pin connector C202 (located under instrument panel, near base of steering column). Using DVOM, check resistance between harness connector C202 terminals E12 (White/Black wire) and E13 (Purple/White wire). If resistance is less than 20 ohms, go to next step. If resistance is 20 ohms or more, go to step 4.
- Leave DVOM connected as specified in step 2. Remove key from ignition switch. If resistance is more than 10,000 ohms, go to step 12. If resistance is 10,000 ohms or less, go to step 13.
- Leave DVOM connected as specified in step 2. If resistance is more than 11.8 k/ohms, go to next step. If resistance is 11.8 k/ohms or less, go to step 6.
- Insert another key into ignition switch. If resistance is less than 11.8 k/ohms, go to step 13. If resistance is 11.8 k/ohms or less, go to step 12.
- Disconnect IPC Blue 24-pin connector C1. Using DVOM, check resistance between IPC harness connector C1, terminals A10 (White/Black wire) and B10 (Purple/White wire). (Scheme 3) If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step 8.
- Repair short between circuits No. 1073 (White/Black wire) and No. 1074 (Purple/White wire) between IPC connector C1 and connector C202. See «WIRING DIAGRAMS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic). Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Using DVOM, check resistance between IPC harness connector C1, terminal A10 (White/Black wire) and ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step 10.
- Repair short to ground in White/Black wire between IPC connector C1 and connector C202. See «WIRING DIAGRAMS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic). Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Using DVOM, check resistance between IPC harness connector C1, terminal B10 (Purple/White wire) and ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step 14.
- Repair short to ground in Purple/White wire between IPC connector C1 and connector C202. See «WIRING DIAGRAMS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic). Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Replace ignition key. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Replace steering column lock cylinder. See appropriate STEERING COLUMN SWITCHES article. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check).
When ignition key is inserted in ignition, resistance of key pellet is measured. Resistance is compared with resistance value stored in IPC memory. DTC B2750 will set if a malfunction occurs in communications between IPC and PCM. Check for any loss of serial data DTCs. If loss of serial data DTCs exist, diagnose those DTCs before continuing. When DTC B2750 is set, IPC will display THEFT SYSTEM PROBLEM, CAR MAY NOT RESTART message on driver's message center.
- Using scan tool, check for DTCs. If DTC U1016 is also set, diagnose and repair first. If PCM DTC P1604 is set, diagnose and repair first.
- DTC B2750 may be caused by a password mismatch between IPC and PCM. If this condition exists, PCM DTC P1631 will also be set. Reprogram IPC. See «REPROGRAMMING IPC»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__reprogramming-ipc) under REPROGRAMMING.
When ignition key is inserted in ignition, resistance of key pellet is measured. Resistance is compared with resistance value stored in IPC memory. DTC B2780 will set when IPC determines that one of 15 valid key pellets is detected, but does not match one stored in IPC memory. When DTC B2780 is set, IPC will display STARTING DISABLED, DUE TO THEFT SYSTEM, REMOVE IGNITION KEY message on driver's message center and prevent vehicle from starting. IPC will count down a 3-minute delay sequence. Vehicle will not start for 3 minutes.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Ensure key is clean and free from contamination. Insert key into ignition switch. Start engine. If STARTING DISABLED message is displayed, go to step 4 . If STARTING DISABLED message is not displayed, go to next step.
- Replace key. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Using each valid vehicle ignition key, attempt to start engine. Wait 3 minutes between each attempt. If engine starts, go to step 6 . If engine does not start, go to next step.
- Perform procedure for replacement of lost PASS-Key(R) II ignition keys. See ANTI-THEFT SYSTEMS - DEVILLE & ELDORADO article. Start engine. If engine starts, perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) . If engine does not start, go to next step.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
When ignition key is inserted in ignition, resistance of key pellet is measured. Resistance is compared with resistance value stored in IPC memory. DTC B2781 will set when IPC determines that one of 15 valid key pellets is detected and is good, IPC class 2 vehicle security password report message was sent and acknowledged, and then IPC determines that the one of 15 valid key pellets it detected does not match one stored in IPC memory.
When DTC B2781 is set, IPC will display THEFT SYSTEM PROBLEM, CAR MAY NOT RESTART message on driver's message.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Connect PASS-Key(R) II (VATS) Interrogator (J35628-A) and turn it on. Insert ignition key into PASS-Key(R) II interrogator's ignition switch. If key code reader displays a value of 1 to 15, go to step 4 . If key code reader does not display a value of 1 to 15, go to next step.
- Perform procedure for replacement of lost PASS-Key(R) II ignition keys. See ANTI-THEFT SYSTEMS - DEVILLE & ELDORADO article. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Wait 3 minutes. Turn ignition switch to RUN position. Check for DTCs. If DTC B2781 is current, go to step 7 . If DTC B2781 is not current, go to next step.
- If ignition key is damaged, replace key. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) . If ignition key is okay, recheck system. See «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Wait 3 minutes. Using another valid vehicle ignition key, turn ignition switch to RUN position. Check for DTCs. If DTC B2781 is current, go to next step. If DTC B2781 is not current, perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Check for poor connections in White/Black wire or Purple/White wire between IPC Blue 24-pin connector C1 and ignition lock cylinder. Also check for poor connections at ignition switch. Repair as necessary. If connections are okay, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
Note. This DTC will set in replacement IPC until first valid key is learned by IPC.
When ignition key is inserted in ignition, resistance of key pellet is measured. Resistance is compared with resistance value stored in IPC memory. DTC B2782 will set when IPC does not have a valid key pellet resistance in memory, and a valid resistance was not learned within 2 seconds after ignition is turned on. When DTC B2782 is set, IPC will display PROGRAM PASSKEY message on driver's message center. DTC B2782 will clear when IPC learns and stores a valid key pellet resistance. If DTC B2710 is also set, diagnose and repair first.
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Insert another key into ignition switch. Turn ignition switch to RUN position. Check for DTCs. If DTC B2782 is current, go to next step. If DTC B2782 is not current, go step 4 .
- Replace initial ignition key. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
When ignition key is inserted in ignition, resistance of key pellet is measured. Resistance is compared with resistance value stored in IPC memory. DTC B2783 will set when all 3 key codes or passwords stored in IPC's memory do not match one another, are all ones, or all zeros.
- Check for DTCs. If any other DTC exists, diagnose and repair it first. If no other DTC exists, go to next step.
- Check for proper connections at IPC connectors. If connections are okay, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
IPC determines brake fluid level by monitoring voltage at IPC connector C2, terminal A11 (Pink wire). DTC C1210 will set when IPC detects voltage of more than 4 volts at IPC connector C2, terminal A11 (Pink wire) for one second. When DTC C1210 is set, IPC will illuminate BRAKE warning indicator and display SERVICE BRAKE FLUID SWITCH on driver's message center.
- If BRAKE warning indicator is illuminated and CHECK BRAKE FLUID message is displayed on driver's message center, check for short to ground in Pink wire between IPC Gray 24-pin connector C2 and brake fluid level switch. (Scheme 3)
- Check for open in Pink wire between IPC connector C2 and brake fluid level switch. Also check for open in Black/White wire between brake fluid level switch and ground. If circuits are okay, replace brake fluid level switch.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1016 will set when IPC has sent an SOH message to Powertrain Control Module (PCM), and no SOH message response was sent back for 3 consecutive monitoring cycles. When DTC U1016 is set, PRNDL display will flash, coolant temperature gauge pointer will move to "C" (analog cluster), coolant temperature message will display dashes (digital cluster), and range and fuel economy information will display dashes. DTC U1016 will clear when PCM transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC is current, use a scan tool and attempt to establish communication with PCM. If communication cannot be established, diagnose and repair problem in PCM system. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1040 will set when IPC has sent an SOH message to Electronic Brake and Traction Control Module (EBTCM), and no SOH message response was sent back for 3 consecutive monitoring cycles. DTC U1040 will clear when EBTCM transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- Check for disconnected EBTCM. If EBTCM is disconnected, DTC U1040 will set and ANTI-LOCK warning indicator will illuminate.
- If DTC is current, use a scan tool and attempt to establish communication with EBTCM. If communication cannot be established, diagnose and repair problem in EBTCM system. See appropriate ANTI-LOCK article in BRAKES. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1064 will set when IPC has sent an SOH message to Platform Zone Module (PZM), and no SOH message response was sent back for 3 consecutive monitoring cycles. When DTC U1064 is set, fuel level will default to empty, and range and fuel economy information will display dashes. DTC U1064 will clear when PZM transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC is current, use a scan tool and attempt to establish communication with PZM. If communication cannot be established, diagnose and repair problem in PZM system. See BODY CONTROL MODULES - DEVILLE & ELDORADO article. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1088 will set when IPC has sent an SOH message to Sensing and Diagnostic Module (SDM), and no SOH message response was sent back for 3 consecutive monitoring cycles. When DTC U1088 is set, AIR BAG warning indicator will illuminate and SERVICE AIR BAG message will display on driver's message center. DTC U1088 will clear when SDM transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC is current, use a scan tool and attempt to establish communication with SDM. If communication cannot be established, diagnose and repair problem in air bag system. See appropriate AIR BAG RESTRAINT SYSTEMS article. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1144 will set when IPC has sent an SOH message to cellular phone (PHN), and no SOH message response was sent back for 3 consecutive monitoring cycles. When DTC U1144 is set, PHONE NOT PRESENT message will display on driver's message center when phone steering wheel control button is pressed. DTC U1144 will clear when PHN transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC is current, use a scan tool and attempt to establish communication with PHN. If communication cannot be established, diagnose and repair problem in PHN system. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1152 will set when IPC has sent an SOH message to Air Control Module (ACM), and no SOH message response was sent back for 3 consecutive monitoring cycles. When DTC U1152 is set, outside temperature and set temperature will display dashes. DTC U1152 will clear when ACM transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC is current, use a scan tool and attempt to establish communication with ACM. If communication cannot be established, diagnose and repair problem in ACM system. See appropriate HVAC article. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
Class 2 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 send a State of Health (SOH) message every 5 seconds to other systems. If those systems fail to send an SOH message back, a corresponding DTC will be set.
DTC U1153 will set when IPC has sent an SOH message to Climate Control Panel (CCP), and no SOH message response was sent back for 3 consecutive monitoring cycles. DTC U1153 will clear when CCP transmits a SOH message to IPC.
- If multiple class 2 DTCs are set as current (i.e., U1300, U1301, U1088 or U1153), check for an intermittent short to ground or battery in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC is current, use a scan tool and attempt to establish communication with CCP. If communication cannot be established, diagnose and repair problem in CCP system. See appropriate AIR CONDITIONING & HEATING article. If communication can be established, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) .
- If DTC is history, check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
IPC periodically requests information from other modules on class 2 serial data line. DTC U1255 will set when IPC requests information, but module which has the desired information is not communicating. When DTC U1255 is set, IPC will use default values for information it was requesting. DTC U1255 will clear when requested information is sent to IPC.
- If DTC U1255 is current, clear DTCs and cycle ignition. Check for DTCs. If DTC U1255 is set, ensure that all modules are functioning properly by establishing communications with each module.
- DTC U1255 will set continuously if phone override option is set incorrectly. Ensure phone override option is only being used for a factory-installed phone unit.
- Check for intermittent open in Purple wire between individual control modules. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS.
- If DTC U1255 sets intermittently, phone is factory-installed, and no other cause for code can be determined, turn phone override option off. If DTC U1255 is current, diagnose and repair problem in phone system.
SYMPTOM TESTS
Note. Before performing any IPC testing or diagnostic procedures, ensure that all aftermarket electrical equipment is disconnected from vehicle. If any circuits have been spliced into aftermarket equipment, ensure circuit is operating properly.
Note. For component locations, see COMPONENT LOCATIONS . For wiring and connector terminal identification, see WIRING DIAGRAMS .
CHARGE INDICATOR INOPERATIVE/ALWAYS ON
For diagnosis and repair, see GENERATORS & REGULATORS - "E" & "K" BODIES article.
CHECK COOLANT LEVEL MESSAGE ALWAYS ON
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Connect scan tool. Disconnect coolant level switch connector. Turn ignition switch to RUN position. Using scan tool, read status for coolant level switch in IPC data list. If scan tool displays OFF for coolant level switch input, go to step 3. If scan tool does not display OFF for coolant level switch input, go to next step.
- Repair short in Light Green wire between coolant level switch and IPC Gray 24-pin connector C2, terminal A10. (Scheme 3) Recheck system operation.
- Replace coolant level switch. Recheck system operation.
CHECK WASHER FLUID MESSAGE ALWAYS ON
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Connect scan tool. Disconnect windshield washer fluid level switch connector. Turn ignition switch to RUN position. Using scan tool, read status for washer fluid level switch in IPC data. If scan tool displays OFF for washer fluid level switch input, go to step 3. If scan tool does not display OFF for washer fluid level switch input, go to next step.
- Repair short in Blue/White wire between washer fluid level switch and IPC Gray 24-pin connector C2, terminal B12. (Scheme 3) Recheck system operation.
- Replace washer fluid level switch. Recheck system operation.
CHECK WASHER FLUID MESSAGE INOPERATIVE
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Disconnect windshield washer fluid level switch connector. Connect a fused jumper wire between washer fluid level switch harness connector terminals "A" (Black/White wire) and "B" (Blue/White wire). Turn ignition switch to RUN position. If CHECK WASHER FLUID message is displayed on driver's message center, go to step 6. If CHECK WASHER FLUID message is not displayed on driver's message center, go to next step.
- Disconnect IPC Gray 24-pin connector C2. Connect a test light between IPC harness connector C2, terminal B12 (Blue/White wire) and battery voltage. (Scheme 3) If test light illuminates, go to step 7. If test light does not illuminate, go to next step.
- Connect a fused jumper wire between washer fluid level switch harness connector terminal "B" (Blue/White wire) and ground. If test light illuminates, go to step 5. If test light does not illuminate, go to next step.
- Repair open in Blue/White wire between washer fluid level switch and IPC connector C2. Recheck system operation.
- Repair open in Black/White wire between washer fluid level switch and ground, located behind left kick panel. Recheck system operation.
- Replace washer fluid level switch. Recheck system operation.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
DOOR AJAR MESSAGE ALWAYS ON
Note. For driver's door, see DRIVER DOOR AJAR MESSAGE ALWAYS ON .
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Connect scan tool. Close and open each passenger door. Using scan tool, read status for passenger door jamb switch. If scan tool displays OFF when all passenger doors are closed, go to step 9 . If scan tool does not display OFF when all passenger doors are closed, go to next step.
- Disconnect right front door jamb switch. If DOOR AJAR message is still displayed, go to next step. If DOOR AJAR message is not displayed, go to step 5 .
- Disconnect left rear door jamb switch. If DOOR AJAR message is still displayed, go to next step. If DOOR AJAR message is not displayed, go to step 6 .
- Disconnect right rear door jamb switch. If DOOR AJAR message is still displayed, go to step 8 . If DOOR AJAR message is not displayed, go to step 7 .
- Replace right front door jamb switch. Recheck system operation.
- Replace left rear door jamb switch. Recheck system operation.
- Replace right rear door jamb switch. Recheck system operation.
- Repair short in Black wire between Platform Zone Module (PZM) Brown 24-pin connector C1, terminal A5 and door jamb switches. Recheck system operation.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
DOOR AJAR MESSAGE INOPERATIVE
Note. For driver's door, see DRIVER DOOR AJAR MESSAGE INOPERATIVE.
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Check operation of interior lights. If interior lights operate properly, go to next step. If interior lights do not operate properly, go to step 14.
- Connect scan tool. Close and open right front door. Using scan tool, read status for passenger door jamb switch. If scan tool displays ON when right front door is open, go to step 10. If scan tool does not display ON when right front door is open, go to next step.
- Disconnect Platform Zone Module (PZM) Brown 24-pin connector C1. Connect a test light between PZM harness connector C1, terminal A5 (Black wire) and battery voltage. (Scheme 3) Open all passenger doors to ajar position. If test light illuminates, go to step 15. If test light does not illuminate, go to next step.
- Close all passenger doors. Open right front door to ajar position. If test light illuminates, go to step 8. If test light does not illuminate, go to next step.
- Disconnect right front door jamb switch. Connect a fused jumper wire between right front door jamb switch harness connector terminal "C" (Black wire) and "A" (Black/White wire). If test light illuminates, go to step 7. If test light does not illuminate, go to next step.
- Repair open in Black wire between right front door jamb switch and splice S326 (located in body wiring harness, about 6" from cross vehicle breakout). Recheck system operation.
- Replace right front door jamb switch. Recheck system operation.
- Close right front door. Open right rear door to ajar position. If test light illuminates, go to step 12. If test light does not illuminate, go to next step.
- Disconnect right rear door jamb switch. Connect a fused jumper wire between right rear door jamb switch harness connector terminal "C" (Black wire) and "A" (Black/White wire). If test light illuminates, go to step 11. If test light does not illuminate, go to next step.
- Repair open in Black wire between right rear door jamb switch and splice S326 (located in body wiring harness, about 6" from cross vehicle breakout). Recheck system operation.
- Replace right rear door jamb switch. Recheck system operation.
- Disconnect left rear door jamb switch. Connect a fused jumper wire between left rear door jamb switch harness connector terminal "B" (Black wire) and "D" (Black/White wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 14.
- Repair open in Black wire between left rear door jamb switch and splice S326 (located in body wiring harness, about 6" from cross vehicle breakout). Recheck system operation.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
- Repair open in Black wire between door jamb switches and ground, located behind right kick panel. Recheck system operation.
DRIVER DOOR AJAR MESSAGE ALWAYS ON
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Connect scan tool. Close and open driver's door. Using scan tool, read status for left front door jamb switch. If scan tool displays OFF when driver's door is closed, go to next step. If scan tool does not display OFF when driver's door is closed, go to step 3 .
- Repair short in Gray/Black wire between driver's door jamb switch and Platform Zone Module (PZM) Brown 24-pin connector C1, terminal B6. Recheck system operation.
- Replace driver's door jamb switch. Recheck system operation.
DRIVER DOOR AJAR MESSAGE INOPERATIVE
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. Check operation of interior lights. If interior lights operate properly, go to next step. If interior lights do not operate properly, repair open in Black/White or Black wire between driver's door jamb switch and ground.
- Connect scan tool. Close and open driver's door. Using scan tool, read status for left front door jamb switch. If scan tool displays ON when driver's door is open, go to next step. If scan tool does not display ON when driver's door is open, go to step 4 .
- Repair open in Gray/Black wire between driver's door jamb switch and Platform Zone Module (PZM) Brown 24-pin connector C1, terminal B6. Recheck system operation.
- Replace driver's door jamb switch. Recheck system operation.
Driver's Information Center (DIC) switch changes state of driver message center, and momentarily grounds one of 5 IPC input circuits to release fuel door or trunk compartment lid. If IPC receives more than one input at a time, it will disregard all commands.
- Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS. If all DIC buttons are inoperative, go to step 5 . If not all DIC buttons are inoperative, go to next step.
- Connect scan tool. Press each DIC button. Using scan tool, read status for each DIC button in IPC data. If scan tool displays ON when each DIC button is pressed, go to step 8 . If scan tool does not display ON when each DIC button is pressed, go to next step.
- Disconnect DIC switch connector. Connect a fused jumper wire between DIC switch harness connector terminal No. 15 (Black/White wire) and appropriate terminal for inoperative DIC button. See «WIRING DIAGRAMS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) . Using scan tool, read status for inoperative DIC button in IPC data. If scan tool displays ON, go to step 7 . If scan tool does not display ON, go to next step.
- Repair open in appropriate circuit. See «WIRING DIAGRAMS»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic) . Recheck system operation.
- Disconnect DIC switch connector. Connect a fused jumper wire between DIC switch harness connector terminals No. 13 (Orange wire) and No. 15 (Black/White wire). Using scan tool, read status for RESET button in IPC data. If scan tool displays ON, go to step 7 . If scan tool does not display ON, go to next step.
- Repair open in Black/White wire between DIC switch and ground. Recheck system operation.
- Replace DIC switch. Recheck system operation.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
IPC monitors fuel level data sent by Platform Zone Module (PZM) through class 2 serial data line. IPC will display this information on an analog gauge (analog cluster) or a message display (digital cluster).
Note. When vehicle is operated in diagnostic mode (either vehicle diagnostic mode or using scan tool), fuel signal is not filtered by PZM. IPC may show real time readings, and may be mistaken as an erratic fuel level display.
Connect scan tool. Check for DTCs. If any DTC is current, diagnose and repair as necessary. See SELF-DIAGNOSTIC SYSTEM . If no DTCs are current, diagnose and repair problem in PZM system. See BODY CONTROL MODULES - DEVILLE & ELDORADO article.
HEADLIGHTS SUGGESTED MESSAGE ALWAYS ON
- Check operation of headlights, daytime running lights and twilight sentinel system. See appropriate HEADLIGHTS - AUTOMATIC TWILIGHT SENTINEL article. If headlight systems operate properly, go to next step. If headlight systems do not operate properly, locate and repair problem in headlight system. See appropriate wiring diagram in HEADLIGHT SYSTEMS article.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
SEAT BELT INDICATOR ALWAYS ON
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
- Connect scan tool. Using scan tool, check SDM data list value for FASTEN BELTS. Unbuckle driver's belt. If scan tool does not display ON, go to next step. If scan tool displays ON, locate and repair problem in audible warning system. See appropriate wiring diagram in WARNING SYSTEMS article.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
SEAT BELT INDICATOR INOPERATIVE
- If IPC diagnostic system check was performed, go to next step. If IPC diagnostic system check was not performed, go to «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
- Connect scan tool. Using scan tool, check SDM data list value for FASTEN BELTS. Fasten driver's belt. If scan tool displays ON, go to next step. If scan tool does not display ON, locate and repair problem in audible warning system. See appropriate wiring diagram in WARNING SYSTEMS article.
- Replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
Vehicle Speed Sensor (VSS) uses a permanent magnet alternator to produce an electrical signal of 24,000 pulses per mile to represent vehicle speed. This signal is sent to Powertrain Control Module (PCM), which sends a 4000 pulse-per-mile signal to IPC through circuit No. 817 (Dark Green wire). IPC supplies voltage to circuit No. 817, and PCM pulses circuit to ground to transmit vehicle speed.
- Connect scan tool. Using scan tool, check for PCM DTCs. If DTC P0500 is set, PCM is not able to accurately read vehicle speed signal. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
- Using scan tool, check data for IPD03 (vehicle speed to IPC). If scan tool displays zero and DTC P0500 is not set, malfunction is between IPC and PCM. Using DVOM, check voltage at IPC Blue 24-pin connector C1, terminal B5 (Dark Green wire). (Scheme 3) Voltage should be pulsed. Repair as necessary. Recheck system operation.
- If IPD03 is displaying correct vehicle speed, IPC is receiving and processing vehicle speed information correctly, but is not displaying the information properly. Check for poor connections at IPC connectors. If connections are okay, replace IPC. See «INSTRUMENT PANEL CLUSTER (IPC)»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__instrument-panel-cluster-ipc) under REMOVAL & INSTALLATION. Perform «IPC DIAGNOSTIC SYSTEM CHECK»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic__ipc-diagnostic-system-check) under DIAGNOSTIC TESTS.
- If IPD03 is fluctuating with speedometer gauge, check for poor terminal contact at all electrical connections. If problem is intermittent, wiggle wires to duplicate conditions at time of malfunction. Check for proper routing of circuit No. 817 (Dark Green wire) between IPC connector C1, terminal B5 and PCM Clear 80-pin connector C2, terminal No. 25. (Scheme 3)
- If vehicle speed always reads 8 percent faster than actual speed, IPC may be operating in export mode. Go to «SPEED DISPLAY HIGHER THAN ACTUAL SPEED»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic).
- Erratic speedometer and tachometer displays can be caused by loose or intermittent PCM ground connections. Check for poor connections at PCM and engine ground. Repair as necessary. Recheck system operation.
When Electronically Erasable Programmable Read Only Memory (EEPROM) option Byte No. 2 (override option B) is set for European Economic Community, speedometer tolerance is about 0-8 percent of actual speed.
Verify proper vehicle configuration (especially option byte "B"). See CHANGING IPC OVERRIDE DISPLAY under REPROGRAMMING.
IPC receives tachometer information from Powertrain Control Module (PCM) through circuit No. 121 (White wire). IPC will display this information on an analog gauge (analog cluster) or a message display (digital cluster).
Connect scan tool. Check for DTCs. If any DTCs exist, diagnose and repair as necessary. See SELF-DIAGNOSTIC SYSTEM . If no DTCs exist, check for open or short in White wire between IPC Blue 24-pin connector C1, terminal A5 and PCM Clear 80-pin connector C2, terminal No. 28. Repair as necessary. Recheck system operation.
When Electronically Erasable Programmable Read Only Memory (EEPROM) option Byte No. 2 (override option B) is set for European Economic Community, French Canadian, Japanese, or Saudi Arabian, trip odometer will reset at 1242.6 miles (1999 km), regardless of English/Metric mode in effect.
Verify proper vehicle configuration (especially option byte "B"). See CHANGING IPC OVERRIDE DISPLAY under REPROGRAMMING.
REMOVAL & INSTALLATION
| WARNING | Deactivate air bag system before performing any service operation. See appropriate AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy. |
These 2 units are integral components of instrument cluster. If either unit must be replaced, replace complete instrument cluster assembly. See INSTRUMENT PANEL CLUSTER (IPC) .
Remove headlight switch module from instrument panel by carefully, yet firmly, pulling outward on switch knob while prying on module's opposite side to remove switch from panel. (Scheme 5) Disconnect electrical connectors. Remove switch module. To install, reverse removal procedure.
Scheme 5
INSTRUMENT PANEL CLUSTER (IPC)
Note. When IPC is replaced, speedometer/odometer information needs to be transferred to new IPC by an authorized service center.
- Remove IGN-A5-IPC fuse (10-amp) and BATT-B5-IPC fuse (10-amp) from trunk compartment fuse panel. Remove A3-IGN 1 fuse (10-amp) from engine compartment fuse panel. Remove instrument panel upper trim panel. See «INSTRUMENT PANEL UPPER TRIM PANEL»(/cadillac/deville-concours/i-final-1999-1999/remont/gauges-instrument-panels/#instrument-panel-analog-electronic).
- Disconnect 3 electrical connectors on top of instrument panel cluster. Remove 4 instrument cluster-to-instrument panel screws. (Scheme 6) Remove instrument panel cluster. To install, reverse removal procedure.
Scheme 6
- Using small, flat-bladed tool, pry upward on defroster grille. (Scheme 7) Remove windshield garnish moldings. Remove sunload and headlight auto control sensor from defroster grille. (Scheme 8) Working through defroster grille opening, remove 3 screws retaining upper trim panel.
- Remove 4 heater and A/C vents from front of instrument panel by releasing tab inside vent and pulling outward. Remove 4 screws retaining upper trim panel through vent openings. On DeVille, on passenger side of vehicle, press down on forward edge of trim panel while pulling upward and back on rear edge of panel. On Eldorado, pull upward and back on rear edge of trim panel. On all models, remove upper trim panel. To install, reverse removal procedure.
