Rick,

Any updates on these issues?

The dealership can run a diagnostic test using the DRB3 scan tool on the FCM.

MikeyB

 

the tipm is not alleviating the issue, they have found the harness to the ecm is shorted somewhere. They are wanting to replace the harness but at their cost. They claim they have never seen an issue like this.

They can run a diagnostic, but it wont communicate with the ecm or fcm, they get a ecm data timeout message.

This is starting to look like it could cost me an arm and a leg.

 

hummmm get your self a ohm meter and check each wire from each end of the harness and see what ones shorted out and run a new one or two you could also swap out the fcm and ecm with a known working used one to see even if its not mated to your truck it will run and then at least you know it sometimes is a pin in the computer box or multi pin connector itself with bad solder joint

 

Not sure on the 04's, but on the 06's, the volt meter reads off the drivers side battery. So if the cable that runs between the two gets corroded, it's gonna overcharge the heck out of the pass side battery (18+ volts). But the only code that's got to do with the batteries or cables is the P2509 (Power down data lost error).

The P0517 (high voltage at battery temp sensor) is showing this as a cause:

BATTERY TEMP SENSOR
(K25) SIGNAL CIRCUIT OPEN
(K900) RETURN CIRCUIT OPEN
(K25) SIGNAL CIRCUIT SHORTED
ECM
INTERMITTENT CONDITION

The P0581, cause or causes here:

S/C WIRING HARNESS OBSERVABLE PROBLEM
CLOCKSPRING SIGNAL/GROUND CIRCUIT OPEN
SPEED CONTROL ON/OFF SWITCH
S/C SWITCH SIGNAL CKT SHORTED TO VOLTAGE
S/C SWITCH SIGNAL CIRCUIT OPEN ECM TO CLOCK SPRING
S/C SWITCH SIGNAL CIRCUIT OPEN CLOCKSPRING TO S/C SWITCH
S/C SWITCH GROUND CIRCUIT OPEN CLOCKSPRING TO S/C SWITCH
S/C SWITCH GROUND CIRCUIT OPEN ECM TO CLOCKSPRING
ECM

Please note, both list the ECM as a possible cause.

 

The reason they are getting that data time out message is because the ECM is not being powered to wake up. It has to have ignition voltage to know that the key has been turned on. Get them to run new powers and grounds to the ECM and try the diagnostic again. I would bet my right nut that you will be able to start the truck and get diagnostics. To test it use the test light method like in my last post if it will run the test light it should run the ECM. The other thing that the test light will give you is a wiggle test if you don't have power to the ECM then wiggle the harness and see if it will come back. Nine times out of ten you will find a big green patch of corrosion or a stiff patch in the wire.

 

Use a multimeter not a test light. Test light will turn on at a low voltage level and fool you. I have gone behind folks before and this is where they screwed up.

 

You need to use both test light to pull amperage and a voltmeter to check voltage.

 

check the ends for corrosion then the plugs with a voltmeter for proper voltage the use that with a light to check for voltage the light will glow a certain amount at 12 volts and less bright at 9 volts
good luck

 

Any word on your truck?