P2503-CHARGING SYSTEM OUTPUT LOW
For a complete wiring diagramRefer to Section 8W.
When Monitored:
The engine running. The engine speed greater than 1157 RPM.
Set Condition:
The battery sensed voltage is 1 volt below the charging goal for 13.47 seconds. The PCM senses the battery
voltage turns off the field driver and senses the battery voltage again. Ifthe voltages are the same, the code
is set. One Trip Fault. Three good trips to turn off the MIL.
Possible Causes
EXCESSIVE RESISTANCE IN THE BATTERY POSITIVE CIRCUIT
EXCESSIVE RESISTANCE IN THE CASE GROUND
(K20) GEN FIELD CONTROL CIRCUIT SHORTED TO VOLTAGE
(K20) GEN FIELD CONTROL CIRCUIT OPEN
(K20) GEN FIELD CONTROL CIRCUIT SHORTED TO GROUND
(Z20) GEN GROUND CIRCUIT OPEN
GENERATOR
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
NOTE: Inspect the vehicle for aftermarket accessories that may exceed theGenerator System output.
Ignition on, engine not running.
NOTE: The battery must be fully charged.
NOTE: The Generator belt tension and condition must be checked before continuing.
With a scan tool, read DTCs.
With a scan tool, erase DTCs.
Start the engine.
Allow the idle to stabilize.
Ignition on, engine not running.
With the scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.FUSED B+ CIRCUIT HIGH RESISTANCE
WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands
near the pulleys, belts, or fan. Do notwear loose clothing. Failure to follow these instructions can result in
personal injury or death.
Ignition on, engine not running.
Measure the voltage between the Generator B+ Output Terminal and the Battery+ Post.
Start the engine.
Is the voltage above 0.4 of a volt?
Ye s>>
Repair the excessive resistance in the battery positive circuit between the Generator and Battery.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 3
POWERTRAIN VERIFICATION TEST
For a complete wiring diagramRefer to Section 8W.
Diagnostic Test
1.SELECTING THE PROPER VERIFICATION TEST
The following verification test are for different repairs. Select the appropriate Verification test for the
repair that has been completed.
Speed Control repair
Go To 2
Charging System repair
Go To 3
NVLD System repair
Go To 4
All other repairs
Go To 5
2.POWERTRAIN VERIFICATION TEST 1
NOTE: 1. If this vehicle is equipped with an Electronic Throttle Control system, and the APP Sensors, PCM,
or Throttle Body Assembly have been replaced, use the scan tool to perform the ETC RELEARN function.
NOTE: 2. After completing the Powertrain Verification Test the Transmission Verification Test must be per-
formed.
NOTE: 3. If the PCM has been replaced and the correct VIN and mileage have notbeen programmed, a DTC
will set in the ABS Module, Airbag Module and the SKIM/SKREEM.
NOTE: 4. If the vehicle is equipped with a Sentry Key Remote Entry, Secret Key data must be updated. Refer
to the Service Information for the PCM, SKIM/SKREEM and the Transponder (ignition key) for programming
information. Using the scan tool, program the Secret Key information intothe PCM using the PCM replaced
function under the WCM menu.
5. Inspect the vehicle to make sure that all engine components are properlyinstalled and connected.
6. Connect the scan tool to the data link connector and erase all codes.
7. Turn the speed control ON (if equipped, cruise light will be on).
8. Depress and release the SET Switch when the vehicle speed is greater than35 MPH. The speed control should
engage and hold the selected speed.
9. Press and hold the RESUME/ACCEL Switch. The vehicle speed should increase by at least 2 MPH.
10. Press and hold the COAST switch. The vehicle speed should decrease.
11. Using caution, press and release the brake pedal. The speed control should disengage.
12. Bring the vehicle speed back up to 35 MPH.
13. Press the RESUME/ACCEL switch. The speed control should resume the previously set speed.
14. Hold down the SET switch. The vehicle should decelerate.
15. Make sure vehicle speed is greater than 35 mph and release the SET Switch. The vehicle should adjust and set
a new vehicle speed.
16. Press and release the CANCEL switch. The speed control should disengage.
17. Bring the vehicle speed back up above 35 mph and engage speed control.
18. Turn the Speed Control Off. (Cruise light will be off). The speed control should disengage.
NOTE: OVERSHOOT/UNDERSHOOT FOLLOWING SPEED CONTROL SET.
19. If the vehicle operator repeatedly presses and releases the SET buttonwith their foot off of the accelerator
(referred to as
lift foot set), the vehicle may accelerate and exceed the desired set speed by up to 5 mph (8km/h).
20. It may also decelerate to less than the desired set speed, before finally achieving the desired set speed.
21. The Speed Control System has an adaptive strategy that compensates forvehicle-to-vehicle variations in speed
control cable lengths.
22. When the speed control is set with the vehicles operators foot off of theaccelerator pedal, the speed control
thinks there is excessive speed control cable slack and adapts accordingly.
P0478-HIGH VOLTAGE ON THE ENGINE
BRAKE DRIVER.......................... 1350
P0480-FAN CLUTCH ...................... 1352
P0483-FAN SPEED ....................... 1357
P0500-NO VEHICLE SPEED SENSOR
SIGNAL.................................. 1364
P0513-SKIM INVALID KEY ERROR ......... 1368
P0514-BAT TEMPERATURE SENSOR
RATIONALITY............................ 1370
P0516-LOW VOLTAGE AT THE BAT TEMP
SENSOR................................. 1372
P0517-HIGH VOLTAGE AT THE BAT TEMP
SENSOR................................. 1376
P0521-OIL PRESSURE SWITCH
RATIONALITY............................ 1380
P0524-OIL PRESSURE TOO LOW .......... 1383
P0532-A/C SENDING UNIT VOLTS TOO
LOW..................................... 1385
P0533-A/C SENDING UNIT VOLTS TOO
HIGH.................................... 1391
P0541-LOW VOLTAGE ON THE #1 INTAKE
AIR HEATER RELAY...................... 1396
P0542-HIGH VOLTAGE ON THE #1 INTAKE
AIR HEATER RELAY...................... 1399
P0562-BATTERY VOLTAGE LOW ........... 1402
P0563-BATTERY VOLTAGE HIGH .......... 1406
P0572-LOW VOLTAGE DETECTED AT THE
BRAKE SWITCH.......................... 1409
P0573-HIGH VOLTAGE DETECTED AT THE
BRAKE SWITCH.......................... 1413
P0580-LOW VOLTAGE DETECTED AT THE
SPEED CONTROL SWITCH................ 1416
P0581-HIGH VOLTAGE DETECTED AT THE
SPEED CONTROL SWITCH................ 1420
P0602-CHECKSUM ERROR ............... 1425
P0604-ECM SOFTWARE ERROR .......... 1426
P0606-ECM HARDWARE ERROR .......... 1427
P0607-ECM INTERNAL FAILURE ........... 1428
P0622-GENERATOR FIELD NOT
SWITCHING PROPERLY.................. 1429
P0628-LOW VOLTAGE DETECTED AT THE
FUEL LIFT PUMP......................... 1433
P0629-HIGH VOLTAGE DETECTED AT THE
FUEL LIFT PUMP......................... 1436
P0630-VIN NOT ENTERED ERROR ........ 1439
P0633-SKIM SECRET KEY NOT ENTERED . 1440
P0642-LOW VOLTAGE AT THE #2 SENSOR
SUPPLY CIRCUIT......................... 1441
P0643-HIGH VOLTAGE AT THE #2 SENSOR
SUPPLY CIRCUIT......................... 1445
P0646-LOW VOLTAGE DETECTED AT THE
A/C CLUTCH RELAY...................... 1448
P0647-HIGH VOLTAGE DETECTED AT THE
A/C CLUTCH RELAY...................... 1451
P0652-LOW VOLTAGE AT THE #1 SENSOR
SUPPLY CIRCUIT......................... 1454
P0653-HIGH VOLTAGE AT THE #1 SENSOR
SUPPLY CIRCUIT......................... 1458P0698-ACCELERATOR PEDAL POSITION
SENSOR (APPS) SUPPLY VOLTAGE TOO
LOW..................................... 1461
P0699-ACCELERATOR PEDAL POSITION
SENSOR (APPS) SUPPLY VOLTAGE TOO
HIGH.................................... 1465
P1272-A/C CLUTCH CONTROL CIRCUIT 2
LOW..................................... 1468
P1273-A/C CLUTCH CONTROL CIRCUIT 2
HIGH.................................... 1471
P1274-A/C CLUTCH CONTROL CIRCUIT 2
OPEN.................................... 1475
P1275-A/C CLUTCH CONTROL CIRCUIT 2
OVERCURRENT.......................... 1479
P127C-FUEL PUMP CONTROL CIRCUIT 2
LOW..................................... 1482
P127D-FUEL PUMP CONTROL CIRCUIT 2
HIGH.................................... 1485
P127E-FUEL PUMP CONTROL CIRCUIT 2
OPEN (TIPM)............................. 1489
P0127F-FUEL PUMP CONTROL CIRCUIT 2
OVERCURRENT (TIPM)
................... 1493
P1652-J1850 SHORT TO GROUND ......... 1496
P2121-PPS CONFORMANCE ERROR ...... 1499
P2122-PPS 1 VOLTAGE TOO LOW ......... 1511
P2123-PPS 1 VOLTAGE TOO HIGH ........ 1516
P2127-PPS 2 VOLTAGE TOO LOW ......... 1520
P2128-PPS 2 VOLTAGE TOO HIGH ........ 1525
P2146-BANK 1 (CYLINDERS 1-3) SHORTED
HIGH OR LOW........................... 1529
P2149-BANK 2 (CYLINDERS 4-6) SHORTED
HIGH OR LOW........................... 1537
P2266-WATER IN FUEL (WIF) SENSOR
VOLTAGE TOO LOW...................... 1544
P2269-WATER IN FUEL (WIF) .............. 1547
P2502-CHARGING SYSTEM ERROR ....... 1549
P2503-CHARGING SYSTEM OUTPUT LOW . 1552
P2504-CHARGING SYSTEM OUTPUT HIGH . 1555
P2509-POWERDOWN DATA LOST ERROR . 1559
P2607-LOW VOLTAGE AT THE #2 INTAKE
AIR HEATER RELAY...................... 1563
P2608-HIGH VOLTAGE AT THE #2 INTAKE
AIR HEATER RELAY...................... 1566
P2609-NO VOLTAGE DROP SEEN FROM
INTAKE AIR HEATERS.................... 1569
*CHECKING THE ACCELERATOR PEDAL
SENSOR CALIBRATION................... 1572
*CHECKING THE ECM POWER AND
GROUNDS............................... 1573
* PRESSURE LIMITING VALVE TEST ....... 1574
*ENGINE SURGES ........................ 1575
*ENGINE NO START/HARD START ......... 1578
*FUEL HEATER THERMOSTAT TEST ....... 1581
*IN-TANK FUEL LIFT PUMP FLOW/
DIAGNOSTIC TEST PROCEDURE.......... 1582
*FUEL PUMP RETURN FLOW TEST ........ 1585
*HIGH PRESSURE FUEL PUMP
PERFORMANCE TEST.................... 1586
*INJECTOR RETURN FLOW TEST ......... 1587
P2502-CHARGING SYSTEM ERROR
For a complete wiring diagramRefer to Section 8W.
P2503-CHARGING SYSTEM OUTPUT LOW
For a complete wiring diagramRefer to Section 8W.
P2504-CHARGING SYSTEM OUTPUT HIGH
For a complete wiring diagramRefer to Section 8W.
P0355-IGNITION COIL #5 PRIMARY
CIRCUIT................................. 1948
P0420-1/1 CATALYTIC CONVERTER
EFFICIENCY............................. 1952
P0432-2/1 CATALYTIC CONVERTER
EFFICIENCY............................. 1955
P0441-EVAP PURGE FLOW MONITOR . . . . . 1958
P0442-EVAP LEAK MONITOR MEDIUM
(0.040) LEAK DETECTED.................. 1962
P0443-EVAP PURGE SOLENOID CIRCUIT . . 1968
P0455-EVAP LEAK MONITOR LARGE LEAK
DETECTED............................... 1972
P0460-FUEL LEVEL SENDING UNIT NO
CHANGE OVER MILES.................... 1978
P0462-FUEL LEVEL SENDING UNIT VOLTS
TOO LOW................................ 1979
P0463-FUEL LEVEL SENSOR 1 CIRCUIT
HIGH.................................... 1982
P0500-NO VEHICLE SPEED SIGNAL ....... 1986
P0505-IDLE AIR CONTROL MOTOR
CIRCUITS................................ 1989
P0513-INVALID SKREEM KEY ............. 1994
P0522-OIL PRESSURE CIRCUIT LOW ...... 1996
P0523-OIL PRESSURE CIRCUIT HIGH ..... 2000
P0601-PCM INTERNAL CONTROLLER
FAILURE................................. 2003
P0622-GENERATOR FIELD NOT
SWITCHING PROPERLY.................. 2004
P0645-A/C CLUTCH RELAY CIRCUIT . . ..... 2008
P0801-REVERSE GEAR LOCKOUT CIRCUIT
OPEN OR SHORTED...................... 2012
P1195-O2 SENSOR 1/1 SLOW DURING
CATALYST MONITOR..................... 2016
P1196-O2 SENSOR 2/1 SLOW DURING
CATALYST MONITOR..................... 2019
P126B-ASD CONTROL CIRCUIT 2 LOW .... 2022
P126C-ASD CONTROL CIRCUIT 2 HIGH .... 2026
P126D-ASD CONTROL CIRCUIT 2 OPEN . . . 2030
P126E-ASD CONTROL CIRCUIT
OVERCURRENT.......................... 2034
P1272-A/C CLUTCH CONTROL CIRCUIT 2
LOW..................................... 2038
P1273-A/C CLUTCH CONTROL CIRCUIT 2
HIGH.................................... 2041
P1274-A/C CLUTCH CONTROL CIRCUIT 2
OPEN.................................... 2045
P1275-A/C CLUTCH CONTROL CIRCUIT 2
OVERCURRENT.......................... 2049
P1277-STARTER CONTROL CIRCUIT 2 LOW
(TIPM)................................... 2052
P1278-STARTER CONTROL CIRCUIT 2
HIGH (TIPM).............................. 2055
P1279-STARTER CONTROL CIRCUIT 2
OPEN (TIPM)............................. 2058
P127A-STARTER CONTROL CIRCUIT 2
OVERCURRENT.......................... 2061
P127C-FUEL PUMP CONTROL CIRCUIT 2
LOW..................................... 2064P127D-FUEL PUMP CONTROL CIRCUIT 2
HIGH.................................... 2067
P127E-FUEL PUMP CONTROL CIRCUIT 2
OPEN (TIPM)............................. 2071
P0127F-FUEL PUMP CONTROL CIRCUIT 2
OVERCURRENT (TIPM)................... 2075
P1281-ENGINE IS COLD TOO LONG ....... 2078
P1282-FUEL PUMP/SYSTEM RELAY
CONTROL CIRCUIT....................... 2079
P1294-TARGET IDLE NOT REACHED ...... 2082
P1296-NO 5-VOLTS TO MAP SENSOR ..... 2085
P1297-NO CHANGE IN MAP FROM START
TO RUN.................................. 2089
P1388-AUTO SHUTDOWN RELAY CONTROL
CIRCUIT................................. 2094
P1389-NO ASD RELAY OUTPUT VOLTAGE
AT P C M.................................. 2097
P1391-INTERMITTENT LOSS OF CMP OR
CKP
..................................... 2100
P1398-MIS-FIRE ADAPTIVE NUMERATOR
AT L I M I T................................. 2104
P1486-EVAP LEAK MONITOR PINCHED
HOSE FOUND............................ 2106
P1492-AMBIENT/BATTERY TEMPERATURE
SENSOR VOLTAGE TOO HIGH............. 2110
P1493-AMBIENT/BATTERY TEMPERATURE
SENSOR VOLTAGE TOO LOW............. 2114
P1494-LEAK DETECTION PUMP SWITCH
OR MECHANICAL FAULT.................. 2117
P1495-LEAK DETECTION PUMP SOLENOID
CIRCUIT................................. 2121
P1499-HYDRAULIC FAN SOLENOID
CIRCUIT................................. 2126
P1594-CHARGING SYSTEM VOLTAGE TOO
HIGH.................................... 2130
P1598-A/C PRESSURE SENSOR VOLTAGE
TOO HIGH............................... 2133
P1599-A/C PRESSURE SENSOR VOLTAGE
TOO LOW................................ 2137
P1682-CHARGING SYSTEM VOLTAGE TOO
LOW..................................... 2141
P1687-NO CLUSTER BUS MESSAGE ...... 2146
P1695-BUS MESSAGE FROM BODY
CONTROL MODULE...................... 2148
P1696-PCM FAILURE EEPROM WRITE
DENIED.................................. 2151
*BRAKE SWITCH SENSE STATUS DOES
NOT CHANGE ON THE SCAN TOOL....... 2153
*CANNOT SHIFT INTO REVERSE .......... 2157
*CHECKING A/C SYSTEM OPERATION
WITH NO DTCS.......................... 2159
*CHECKING CHARGING SYSTEM
OPERATION WITH NO DTCS.............. 2163
*CHECKING RADIATOR FAN OPERATION . . 2167
*CHECKING THE PCM POWER AND
GROUNDS............................... 2169
B2277–CAN GATEWAY INTERNAL
(GATEWAY).............................. 2172
U0001–CAN C BUS CIRCUIT (GATEWAY) . . . 2172