Alternator & Regulator: Diagnosis Dodge Intrepid I

TROUBLE SHOOTING

Note. See TROUBLE SHOOTING - BASIC PROCEDURES article in the GENERAL INFORMATION Section.

ON-VEHICLE TESTING

Note. ALTERNATOR OUTPUT BAT WIRE RESISTANCE TEST will show amount of voltage drop across alternator output wire between alternator BAT terminal and positive battery post.

Alternator Output BAT Wire Resistance Test

1. Before performing this test, ensure battery is fully charged. Using ohmmeter check alternator ground circuit. Resistance between alternator case and engine ground should be less than 0.3 ohm. If resistance is more than 0.3 ohm, clean surface between alternator and mounting bracket.
2. Using an external voltmeter (0-18 volts minimum), connect positive voltmeter lead to alternator BAT terminal. (Scheme 1) Connect negative lead to positive battery cable. Connect tachometer to engine. Fully engage parking brake and place gear selector in Neutral position. Start engine and run for 10 minutes.
3. Operate blower motor on high speed and turn headlights on high beam. Increase engine speed to 2400 RPM. Observe voltmeter. Voltage drop should not be more than 0.8 volt.
4. If voltage drop is more than 0.8 volt, inspect, clean and tighten all connections between alternator BAT terminal and positive battery post. Voltage drop test may be performed at each connection to locate connection with excessive resistance. If resistance tests are satisfactory, reduce engine speed, turn off blower motor, headlights and ignition switch.

Scheme 1

Note. CURRENT OUTPUT TEST determines if alternator is capable of delivering its rated current output.

Current Output Test

1. Before performing this test, ensure battery is fully charged. Connect voltmeter leads across battery terminals. Record voltage with ignition switch and all accessories off. Fully engage parking brake and place gear selector in Park position.
2. Start engine and operate at normal operating temperature. Record voltage with engine speed at 1500 RPM and no electrical load. Voltage should not be more than 2.5 volts above battery voltage previously recorded in step 1). If is more than 2.5 volts above previously recorded battery voltage, proceed to «TEST TC-52A, CHARGING SYSTEM VOLTAGE HIGH»(ref-10846-S22228689392001011700000) under SELF-DIAGNOSTIC TESTS.
3. Record voltage with engine speed at 2000 RPM, blower motor on high and headlights on high beam. Voltage should be more than 0.5 volt above battery voltage previously recorded in step 1). If voltage is less than 0.5 volt above previously recorded battery voltage, go to «TEST TC-51A, CHARGING SYSTEM VOLTAGE LOW»(ref-10846-S40397903942001011700000) under SELF-DIAGNOSTIC TESTS. If voltage tests are satisfactory, reduce engine speed, turn off blower motor, headlights and ignition switch.

BENCH TESTING

Bench Testing information is not available.

SYSTEM DIAGNOSIS

The self-diagnostic capabilities of this system, if properly used, can simplify testing. Powertrain Control Module (PCM) monitors several different engine control system circuits.

If a problem is sensed with a monitored circuit, Malfunction Indicator Light (MIL) will illuminate and PCM will enter limp-in mode. In limp-in mode, PCM attempts to compensate for particular component failure by substituting information from other sources. This allows vehicle operation until proper repairs are made.

Once trouble codes are known, to determine the questionable circuit, refer to CHARGING SYSTEM TROUBLE CODES table under ENTERING ON-BOARD DIAGNOSTICS.

Perform circuit tests to repair or replace components as required. If problem is repaired or ceases to exist, the PCM will cancel that trouble code after 50 ignition on/off cycles. To clear codes, refer to appropriate ERASING TROUBLE CODES procedure under ENTERING ON-BOARD DIAGNOSTICS .

A specific trouble code results from a particular system failure. Components in that system are not necessarily the reason for that failure. The trouble code does not condemn a specific component, it indicates a circuit malfunction.

DIAGNOSTIC PROCEDURE

Note. When using diagnostic tests, DO NOT skip any test steps or incorrect diagnosis may result.

Before proceeding with diagnosis, the following precautions must be followed

1. Vehicle must have a fully charged battery and functional charging system (belt installed and all wiring connected).
2. DO NOT backprobe PCM connector. Probe PCM connector from terminal side.
3. DO NOT cause short circuits when performing electrical tests. This will set additional trouble codes, making diagnosis of original problem more difficult.
4. DO NOT use a test light in place of a voltmeter.
5. ALWAYS repair lowest trouble code number first when using MIL method. Repair first trouble code displayed when using DRB.
6. ALWAYS perform «TEST CH-VER, VERIFICATION PROCEDURE»(ref-10846-S09224813652001011700000) after repairs are made.
7. ALWAYS disconnect DRB after completing testing, before starting any repairs and before charging battery.

ENTERING ON-BOARD DIAGNOSTICS

Reading Trouble Codes

1. Trouble codes may be read by using Malfunction Indicator Light (MIL) on instrument panel or with DRB. See either MIL DIAGNOSTIC MODE or DIAGNOSIS USING DRB headings below. Using DRB will provide a more complete diagnosis.
2. If trouble codes are not present and DRB is used, proceed to «TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES»(ref-10846-S37510182952001011700000) under SELF-DIAGNOSTIC TESTS.

Note. The PCM cannot diagnose every charging system problem. If a failure still exists after performing self-diagnostic procedures, go to ON-VEHICLE TESTING .

Trouble Code Explanation

1. See «CHARGING SYSTEM TROUBLE CODES»(ref-10846-S04300643442001011700000) table for charging system-related failures.
2. Code 12 will set if battery feed to PCM has been disconnected within last 50 starts. PCM monitors circuit when ignition is on.
3. Code 41 will set if PCM output for alternator field does not respond to voltage regulator control signal. PCM monitors circuit when ignition is on.
4. Code 46 will set if battery sense voltage is more than one volt above desired control voltage for more than 20 seconds. PCM monitors this signal whenever engine is running.
5. Code 47 will set if battery sense voltage is more than one volt below desired control voltage for more than 20 seconds, and active test indicates an alternator problem. PCM monitors this signal whenever engine speed is above 1500 RPM.

CHARGING SYSTEM TROUBLE CODES

Note. Only charging system-related codes are listed here. For engine-related codes, see TESTS W/CODES - 3.3L article in the ENGINE PERFORMANCE Section for other codes.

MIL Diagnostic Mode

1. Start engine (if possible). Move transmission shift lever through all positions, ending in Park. Turn A/C switch on and then off (if equipped).
2. Turn engine off. Without starting engine again, turn ignition on, off, on, off and on. MIL will come on for 2 seconds as a bulb check, followed by trouble codes. Record 2-digit trouble codes as displayed by flashing MIL.
3. For example, Code 23 is displayed as flash, flash, 4 second pause, then flash, flash, flash. After a slightly longer pause, any other codes stored are displayed in numerical order.
4. Once MIL begins to flash trouble codes, it cannot be stopped. Code 55 indicates end of trouble code display. Go to step 1) to enter diagnostic mode again. For more information on vehicle self-diagnostics, see «TESTS W/CODES - 3.3L»(ref-10827) article in the ENGINE PERFORMANCE Section.
5. Refer to «CHARGING SYSTEM TROUBLE CODES»(ref-10846-S04300643442001011700000) table to translate trouble code number to a circuit description (same description is displayed in DRB display). Once trouble area is identified, refer to appropriate charging system test procedures under «ON-VEHICLE TESTING»(ref-10846-S37265269152001011700000) .

Note. MIL cannot be used to perform actuation test mode, sensor test modes or engine running test.

Erasing Trouble Codes Using MIL

Trouble codes can only be manually erased by using DRB. After 50 ignition switch cycles (ON-OFF-ON), PCM memory will erase any trouble codes that have not reoccurred.

Diagnosis Using DRB

DRB is used as part of a charging system diagnostic procedure when performing TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES through TEST CH-VER, VERIFICATION PROCEDURE under SELF-DIAGNOSTIC TESTS.

DRB Diagnostic Mode

1. Turn ignition off. Connect DRB to Data Link Connector (DLC). DLC is located under center of dash, right of steering column.
2. Start engine (if possible). Move transmission lever through all positions, ending in Park. Turn A/C switch on and off (if equipped).
3. Turn engine off. Without starting engine again, turn ignition on. Enter CHARGING MENU. To enter CHARGING MENU see DRB TEST FUNCTIONS. At CHARGING MENU, press "2" key (READ TROUBLE CODES). Press ENTER key. After trouble codes are accessed, refer to procedures in «TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES»(ref-10846-S37510182952001011700000) under SELF-DIAGNOSTIC TESTS.

Erasing Trouble Codes Using DRB

1. Record all trouble codes before erasing. Press ATM key. At DRB display, press "2" (ERASE) key. DRB will display: ERASE TROUBLE CODES ARE YOU SURE? (ENTER TO ERASE). Press ENTER key to erase all trouble codes.
2. When DRB is finished erasing trouble codes, it will display TROUBLE CODES ERASED. This display will remain until ATM key is pressed. After ATM key is pressed, display will return to CHARGING MENU screen.

DRB TEST FUNCTIONS

Note. DO NOT touch DRB keypad during DRB power-up sequence, or an ERROR message will result.

1. To access trouble code descriptions, and perform diagnostic tests using DRB, DRB must be in the CHARGING MENU display. To reach CHARGING MENU, turn ignition off. Connect DRB to Data Link Connector (DLC). DLC is located under center of dash, right of steering column.
2. Turn ignition switch to RUN position. All DRB character positions will illuminate and copyright information will appear on screen for several seconds. If DRB screen is blank or any error messages appear, refer to «DRB PROBLEMS & ERROR MESSAGES»(ref-10846-S21586873522001011700000) under SELF-DIAGNOSTIC SYSTEM.
3. After several seconds DRB menu will appear. At DRB menu, press "4" (SELECT SYSTEM) key. Press ENTER key. At SELECT SYSTEM menu, press "1" (ENGINE) key. Press ENTER key. DRB menu will appear, indicating engine year and size, type of transmission and PCM part number.
4. After several seconds AIR COND menu will appear. Press "1" (WITH A/C) or press "2" (WITHOUT A/C). DRB display will change to ENGINE SYSTEMS menu. At ENGINE SYSTEMS menu, press "2" (CHARGING) key. Press ENTER key.
5. Display will change to CHARGING MENU. At CHARGING MENU of engine diagnostic program, specific test functions programmed into DRB can be performed. The following DRB modes can be accessed: READ TROUBLE CODES, STATE DISPLAYS, ACTUATOR TEST and ADJUSTMENTS.

SYSTEM TEST Mode

This function is not available in engine diagnostics program.

READ TROUBLE CODES Mode

This function allows the user to read and erase trouble codes. A trouble code counter will appear along with trouble code displayed on DRB. For example, DRB will display 1 OF 4 TROUBLE CODES. PCM will store up to 8 trouble codes. Trouble codes are numbered in reverse order of their setting. The most recent trouble code to occur will be number one. Vehicles without A/C will always have A/C CLUTCH RELAY CKT (circuit) stored in memory. This trouble code will always be number one if vehicle is not equipped with A/C. If no trouble codes are stored, DRB will display NO TROUBLE CODES DETECTED and start counter will show 0 STARTS SINCE ERS.

A start counter will appear below DRB trouble code counter display. Start counter counts number of times vehicle has started since trouble code(s) was set, erased or battery was disconnected. This helps determine if failure is intermittent. Memory space limits start counter to first 3 trouble codes. Start counter of zero equals a hard trouble code. Start counter number more than one indicates an intermittent trouble code. Start counter will count up to 255 starts. If no trouble codes are stored, DRB will display NO TROUBLE CODES DETECTED and start counter will show 0 STARTS SINCE ERS.

ACTUATOR TEST Mode

This function allows user to check for proper operation of output circuits or devices, which PCM cannot internally recognize. DRB allows PCM to activate these outputs or devices, allowing an observer to verify proper operation.

Most tests available in this mode provide an audible or visual indication of device operation (click of relay contacts, spray fuel, etc.). With exception of an intermittent condition, if a device functions properly during its test, it can be assumed that device, wiring and its driver circuit are functioning properly.

RAM TEST FAILURE Message

See TESTS W/CODES - BODY CONTROL COMPUTER article in the ENGINE PERFORMANCE Section.

KEY PAD TEST FAILURE Message

See TESTS W/CODES - BODY CONTROL COMPUTER article in the ENGINE PERFORMANCE Section.

TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION in TESTS W/CODES - 3.3L article in the ENGINE PERFORMANCE Section.

Note. Battery must be fully charged before proceeding.

1. Attempt to start engine. If necessary, crank engine for up to 10 seconds. Connect DRB to data link connector. Record DRB trouble codes. If DRB screen shows no response, go to TEST NS-6A, CORRECTING NO RESPONSE CONDITION in «TESTS W/CODES - 3.3L»(ref-10827) article in the ENGINE PERFORMANCE Section.
2. If trouble codes are displayed, see DRB TROUBLE CODES table for charging system trouble codes, or see TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES in «TESTS W/CODES - 3.3L»(ref-10827) article in the ENGINE PERFORMANCE Section for all other trouble codes. If no codes are displayed, go to «TEST CH-1A, CHECKING CHARGING SYSTEM CONTROLS»(ref-10846-S29972954852001011700000) .

DRB TROUBLE CODES

TEST CH-1A, CHECKING CHARGING SYSTEM CONTROLS

Note. Perform TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES before proceeding. After each repair, perform the TEST CH-VER, VERIFICATION PROCEDURE .

1. Verify condition of battery. Ensure battery does not show signs of freezing, leakage, loose battery posts, or low electrolyte/water level. Inspect alternator belt tension and condition. Replace belt if necessary.
2. Start engine. Using DRB, set engine speed to 2000 RPM for 30 seconds. Return engine speed to idle and read trouble codes. If trouble codes are present, go to DRB TROUBLE CODES table. If no trouble codes are present, turn engine off with ignition on. Using DRB, actuate alternator field.
3. Using DRB in voltmeter mode, backprobe field terminal (Dark Green wire) and then Auto Shutdown (ASD) relay output terminal (Dark Green/Orange wire) at rear of alternator. (Scheme 1) Voltage should cycle from zero to battery voltage every 1.4 seconds.
4. While observing DRB voltage cycle display, wiggle wiring harness in sections from rear of alternator to powertrain control module and to auto shutdown relay. If there is any interruption in voltage cycle display, repair wiring where interruption occurred. If there is no interruption of voltage cycle display, test is complete.

TEST TC-49A, BATTERY TEMP. SENSOR VOLTS OUT OF LIMIT

Note. After repair, perform TEST CH-VER, VERIFICATION PROCEDURE .

Using DRB, erase trouble codes. Turn ignition on and wait 10 seconds. Using DRB, read trouble codes. If BATTERY TEMPERATURE SENSOR VOLTAGE (Code 44) returns, replace powertrain control module. If BATTERY TEMPERATURE SENSOR VOLTAGE (Code 44) does not return, system is operating properly at this time. Test is complete.

TEST TC-50A, ALTERNATOR FIELD NOT SWITCHING PROPERLY

Note. After repair, perform TEST CH-VER, VERIFICATION PROCEDURE .

1. Turn ignition on, engine off. Using DRB, actuate Auto Shutdown (ASD) fuel system. Using DRB in voltmeter mode, backprobe ASD relay output terminal (Dark Green/Orange wire) at rear of alternator. (Scheme 1) If voltage is less than 10 volts, repair open in Dark Green/Orange wire to alternator.
2. If voltage is more than 10 volts, backprobe field terminal (Dark Green wire) at rear of alternator. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, go to step 5).
3. Using DRB, stop ASD fuel system actuation test. Turn ignition off. Disconnect and inspect Powertrain Control Module (PCM) connector and terminals. PCM is located under air cleaner. Disconnect and inspect alternator field circuit connector at rear of alternator. (Scheme 1) If any connector is damaged, repair or replace as necessary.
4. If all connectors are okay, leave PCM and alternator field circuit connectors disconnected. Using an external ohmmeter, check resistance of Dark Green wire between alternator field circuit connector and PCM connector terminal No. 20. (Dark Green wire). (Scheme 2) If resistance is less than 5 ohms, replace PCM. If resistance is more than 5 ohms, repair open in Dark Green wire.
5. Using DRB, stop ASD fuel system actuation test. Turn ignition off. Disconnect and inspect PCM connector and terminals. PCM is located under air cleaner. Disconnect and inspect alternator field circuit connector at rear of alternator. If any connector is damaged, repair or replace as necessary.
6. If all connectors are okay, leave alternator field circuit connector disconnected. Using an external ohmmeter, connect one lead to field terminal and one lead to ASD relay output terminal at rear of alternator. If resistance is more than 5 ohms, replace alternator.
7. If resistance is less than 5 ohms, put DRB in ohmmeter mode. Probe alternator connector field terminal (Dark Green wire). If resistance is more than 5 ohms, replace PCM. If resistance is less than 5 ohms, repair short to ground in Dark Green wire.

Scheme 2

TEST TC-51A, CHARGING SYSTEM VOLTAGE LOW

Note. After repair, perform TEST CH-VER, VERIFICATION PROCEDURE .

1. Using DRB, read VOLTAGE GOAL. If voltage goal is more than 15.1 volts, replace Powertrain Control Module (PCM). If voltage goal is less than 15.1 volts, using an external voltmeter, connect positive lead to alternator BAT terminal. (Scheme 1) Connect voltmeter negative lead to battery positive terminal. CAUTION: Ensure all test equipment and wires are clear of moving engine parts when starting engine.
2. Start engine. If voltage is more than 0.4 volt, repair Black/Gray wire between alternator and battery to eliminate high resistance. If voltage is less than 0.4 volt, turn ignition off. Using external voltmeter, connect positive lead to alternator case and voltmeter negative lead to negative battery terminal.
3. Start engine. If voltage is more than 0.1 volt, repair Black wire between alternator and battery to eliminate high resistance. If voltage is less than 0.1 volt, start engine and manually set engine speed to 1600 RPM.
4. Using DRB, read VOLTAGE GOAL and voltage. Compare readings. If voltage difference is more than one volt, replace alternator. If voltage difference is less than one volt, turn engine off leaving ignition on and go to next step.
5. Using DRB, actuate alternator field. Using DRB in voltmeter mode, backprobe field terminal (Dark Green wire) at rear of alternator. Voltage should cycle from 2 volts to battery voltage every 1.4 seconds.
6. While observing DRB voltage cycle display, wiggle field terminal wiring harness in sections from rear of alternator to PCM and to auto shutdown relay. If there is any interruption in voltage cycle display, repair wiring where interruption occurred.
7. If there is no interruption of voltage cycle display, stop alternator field actuation using DRB. If battery was not disconnected or dead at any time before or during testing, system is operating properly. Test is complete.
8. If battery cables were disconnected or vehicle had a dead battery before testing began, road test vehicle for minimum of 5 minutes, at 25 MPH or more. After completion of road test, leave engine on. Read all trouble codes. Turn ignition off and perform appropriate test(s). Repair any trouble codes now displayed. If no trouble codes are displayed, test is complete.

TEST TC-52A, CHARGING SYSTEM VOLTAGE HIGH

Note. After repair, perform TEST CH-VER, VERIFICATION PROCEDURE .

1. Turn ignition on, engine off. Using DRB, actuate Auto Shutdown (ASD) fuel system. Using DRB in voltmeter mode, backprobe field terminal (Dark Green wire) at rear of alternator. If voltage is more than 10 volts, go to step 5).
2. If voltage is less than 10 volts, using DRB, stop ASD fuel system actuation test. Turn ignition off. Disconnect and inspect Powertrain Control Module (PCM) connector and terminals. PCM is located under air cleaner. Disconnect and inspect alternator field circuit connector at rear of alternator. If any connector is damaged, repair or replace as necessary.
3. Leave PCM connector disconnected. Using DRB in ohmmeter mode, probe PCM connector terminal No. 20. (Dark Green wire). (Scheme 2) If resistance is less than 5 ohms, repair short to ground in Dark Green wire between PCM connector and alternator. If resistance is more than 5 ohms, probe either the alternator field terminal or the ASD relay output terminal at rear of alternator.
4. If resistance is less than 5 ohms, replace alternator. If resistance is more than 5 ohms, replace PCM.
5. If voltage is more than 10 volts in step 1), using DRB, stop ASD fuel system actuation. With ignition on and engine off, read DRB VOLTAGE GOAL. If voltage goal is less than 13 volts, replace PCM. If voltage goal is more than 13 volts, start engine and manually set idle to 1600 RPM. Using DRB, read VOLTAGE GOAL and voltage. Compare readings. If necessary, watch readings for up to 5 minutes looking for a one volt or more difference.
6. If voltage difference is more than one volt, replace PCM. If voltage difference is less than one volt, turn engine off leaving ignition on and go to «TEST CH-1A, CHECKING CHARGING SYSTEM CONTROLS»(ref-10846-S29972954852001011700000).

TEST CH-VER, VERIFICATION PROCEDURE

1. Inspect and ensure that all engine components are connected. If other trouble code(s) was previously present and has not yet been corrected, see «TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES»(ref-10846-S37510182952001011700000) . If Powertrain Control Module (PCM) has been changed and vehicle is equipped with Vehicle Theft Security System (VTSS), turn ignition on then off at least 20 times to activate VTSS. If PCM has not been changed, using DRB, erase trouble codes. Using DRB, reset all values in adaptive memory and disconnect DRB.
2. Ensure no other charging system problems remain by doing the following: Turn on A/C and blower motor (if equipped with A/C). Drive vehicle for no less than 5 minutes and attain a speed of 40 MPH. Ensure transmission shifts through all gears. After completion of road test, turn engine off. Start engine and idle for no less than 2 minutes. Turn engine off. Connect DRB to DLC and read trouble codes.
3. If previously repaired trouble code has reset, repair is incomplete. Check all related TECHNICAL SERVICE BULLETINS and return to «TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES»(ref-10846-S37510182952001011700000) if needed. If other codes are present, see «TEST TC-1A, CHECKING SYSTEM FOR TROUBLE CODES»(ref-10846-S37510182952001011700000) . If there are no other trouble codes, repair is complete.