Jeep PCM problem
Power Control module looses communication with other modules in jeep.
2007 compass it wouldn't crank at all, when i scan it, it says "A communication error has occurred with the ECU", when i scan the tcm its says lost comm with ecu pcm. i got another ecu same thing.
Troubleshooting:
As per problem described it sounds like no modules are communicating with the PCM but it has been replaced with a known good unit?
First make sure all fuses are good. If the PCM loses a power or ground feed that will prevent it from waking up, operating and communicating.
Its suggested to do load test the PCM powers and grounds.
The procedure to do this would be with a couple jumper wires and a headlamp or fog lamp bulb. The bulb should light as brightly as if you connected it straight to the battery, if it doesn't light or is dim then you know that particular power or ground has a wiring issue.
If you find the powers and grounds to be ok you'll want to check the CAN C bus voltages at the PCM connector, each wire should be about 2.5v with the key on.
If all checks ok but the PCM won't come alive then it could have a short somewhere in the engine compartment that is taking it down. If the sensor ground circuit shorts to voltage (wiring or internally in a sensor) then it could prevent the PCM from waking up, or if a 5v reference circuit shorts to ground it could do the same.
Many a times on such cases you see wire get cut or crimped somewhere loosing the voltage.
So inspect each and every wire visually.
This types of problem sometimes takes long to get solved.
This details will help.
Thanks.
ALSO VIEW THIS RELATED:
For Car parts and diagrams:
CAR MANUAL GUIDE
FOR FREE MANUALS AND GUIDES: ---
Car repair guide?
For all types of car repair help:
Car Backfires
For car repair How to guides:
|
|
OVERHEATING: Radiator Fan Not Working
Engine Cooling Fan not Working
"Radiator fan" "Engine Fan"
"COOLING FAN WILL NOT TURN OFF"
LIFT GATE / TAIL GATE ISSUES
TRUNK WILL NOT OPEN
CAR ALARM ISSUES
Car starter removal, Starter motor testing, Starter repairs, Starter
solenoid, Starter wiring,
DOOR PANEL REMOVAL, car door panel, door panel components, front
door panel, rear door panel,
HEATER CORE REPLACEMENT, HEATER CORE REMOVAL, TROUBLESHOOT HEATER CORE , FLUSH HEATER CORE ,
CAR POWER SEAT, ELECTRIC SEAT, POWER SEAT WILL
NOT WORK , SEAT WILL NOT GO FORWARD,
For all types
of---------
Timing belt
routing diagrams for cars and trucks?
==========
For all types of
--------
Drive belt
routing diagrams for cars and trucks?
stalling issues:
Engine stalls, car stalls while starting, vehicle stalls while
starting, Engine stalls and dies, Car stalls and stops,
CRUISE CONTROL Not working, cruise control replacing,
troubleshooting cruise control problems,
TRANSMISSION PROBLEMS:
NO REVERSE ON TRANSMISSION
GEAR SHIFT ISSUES
Transmission fluid leak, transmission gears slip,
TRANSMISSION REPLACING AND TROUBLESHOOTING, INSPECTING
TRANSMISSION COMPONENTS, TRANSMISSION FAILURES, OD WARNING LIGHT,
TRANSMISSION FLUID FILLING, WHERE TO FILL TRANSMISSION FLUID,
AUTOMATIC TRANSMISSION FLUID, NO TRANSMISSION DIPSTICK,
WINDSHIELD WIPERS, WINDSHIELD WIPERS NOT WORKING,WIPER MOTOR
MAKING NOISE,NO WIPERS,WIPER FLUID LEAKS,WIPER FUSE AND RELAY,
COOLANT LEAK ISSUES, COOLANT LEAK PROBLEMS, COOLANT SENSOR, LOW COOLANT ,
BRAKE LIGHTS NOT WORKING, REPAIRING BRAKE LIGHTS, NO BRAKE LIGHTS,
CHECK ENGINE LIGHT,ENGINE WARNING LIGHT FLASHING,ENGINE LIGHT ON
DASH,DASHBOARD WARNING LIGHT,ECM ERROR CODES,
DASHBOARD WARNING LIGHTS ARE ON, ENGINE LIGHT ON DASH,WARNING
LIGHTS STEADY ON DASH,RESET DASH BOARD WARNING INDICATOR,
KEYFOB PROGRAMMING, REPROGRAMMING CAR KEY, KEYLESS ENTRY
RESET,ANTITHEFT WILL NOT LET CAR TO START, ANTI THEFT ISSUES, KEYFOB NOT
WORKING, KEYLESS ENTRY QUIT WORKING,
IGNITION KEY WILL NOT RELEASE, IGNITION KEY STUCK UP, KEY WILL NOT
COME OUT OF IGNITION, FAULTY IGNITION KEY LOCK CYLINDER, REPLACING IGNITION
CYLINDER,
HEATER ISSUES:
HEATER NOT BLOWING COLD,NO HOT AIR FROM HEATER,A/C BLOWS HOT AIR,A/C
NOT BLOWING COLD, COLD AIR FROM HEATER,BLEND DOOR ACUTATOR CLOSED,HVAC UNIT NOT
OPERATING,
HEATER NOT BLOWING COLD,NO HOT AIR FROM HEATER,A/C BLOWS HOT
AIR,A/C NOT BLOWING COLD, COLD AIR FROM HEATER,BLEND DOOR ACUTATOR CLOSED,HVAC
UNIT NOT OPERATING,
STEERING ISSUES:
POWER STEERING TROUBLESHOOTING, STEERING SQUEAKS, POWER STEERING
FLUID LEAKS, FAULTY POWER STEERING PUMP, POWER STEERING NOT WORKING, POWER
STEERING BELT,
VEHICLE STARTING ISSUE:
CAR NO STAR T: ENGINE NOT TURNING
OVER:
No comments:
Post a Comment