Need electrical help over charging

Tried another PCM today out of another early 04 auto 4x4 like mine today. Mine has build date of 11/03 PCM I tried had truck build date of 9/03 truck would only crank not start.
 
slor1de said:
Tried another PCM today out of another early 04 auto 4x4 like mine today. Mine has build date of 11/03 PCM I tried had truck build date of 9/03 truck would only crank not start.
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PCM or ECM?

ECM is on the side of the engine.
 
slor1de said:
Tried another PCM today out of another early 04 auto 4x4 like mine today. Mine has build date of 11/03 PCM I tried had truck build date of 9/03 truck would only crank not start.
Click to expand...
LOL
Gibson said:
PCM or ECM?

ECM is on the side of the engine.
Click to expand...

The ECM keeps the engine from starting unless the vin is matched. We replace them and everytime the vin needs reset with a DRBIII.
 
slor1de said:
Tried another PCM today out of another early 04 auto 4x4 like mine today. Mine has build date of 11/03 PCM I tried had truck build date of 9/03 truck would only crank not start.
Click to expand...

:doh:
 
LReiff said:
The ECM keeps the engine from starting unless the vin is matched. We replace them and everytime the vin needs reset with a DRBIII.
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Wrong. I put an 03 ecm on my 04 and it started right up. The gauges didn't work until I flashed it, but the engine ran fine.
 
duck_04 said:
Wrong. I put an 03 ecm on my 04 and it started right up. The gauges didn't work until I flashed it, but the engine ran fine.
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Apparently your truck does not have a security system or its disabled. With a security system the vin in the ecm must match the vehicle to allow the engine to run.
 
LReiff said:
Apparently your truck does not have a security system or its disabled. With a security system the vin in the ecm must match the vehicle to allow the engine to run.
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I see now. If the vehical has the security disabled then an ECM swap will not require a reflash with proper VIN. Correct?
 
If you are still having the problem mine did the same somewhat but no codes. Clean all your battery terminals (I know you said you did) and change out the clamping bolts for the ends. The wire that runs from pass batt to driver batt mounts to a stud and can cause the driverside to not charge properly. The ecm reads voltage to tell the alternator to charge from a battery temp sensor located under the driverside battery. This was the problem with mine. Put a new one in and all is now good for charging.
 
MCDIESEL said:
If you are still having the problem mine did the same somewhat but no codes. Clean all your battery terminals (I know you said you did) and change out the clamping bolts for the ends. The wire that runs from pass batt to driver batt mounts to a stud and can cause the driverside to not charge properly. The ecm reads voltage to tell the alternator to charge from a battery temp sensor located under the driverside battery. This was the problem with mine. Put a new one in and all is now good for charging.
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He would have figured that out after a replacement ecm didn't fix it. :lolly:
 
Dumb question. I always thought a good charging voltage was 13.2-14.5. I put the multimeter on my batteries and got 15.00v on passenger side and 15.02 on the drivers side. Isn't that too high?
 
dixon700 said:
Dumb question. I always thought a good charging voltage was 13.2-14.5. I put the multimeter on my batteries and got 15.00v on passenger side and 15.02 on the drivers side. Isn't that too high?
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Mine charges at 14.9 when there's no electrical load on it.
 
So my 15v could be normal. Just seems like a lot more than I've always been used to...
 
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