525 Problems
06-16-2010, 04:37 AM
#11
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No starts are the easiest fault to troubl;e shoot on any efi system. The reason being that the problem IS there right now.
In order to start and run, the PCM needs several things to happen and then it either responds or it doesn't.
Step one is to verify when the ignition key is turned to the ON position, does the fuel pump come on for approx 2 seconds to prime the system. If so, the PCM is getting ignition voltage, the FP relay and FP both work. If not, either the PCM remains un powered, has very poor ground, the relay is unpowerd or ungrounded by the PCM or it relay is ng or the pump is NG. Just need to follow back from the pump to see where the power stiops and fix the issue.
For igniton to occur, the PCM needs to see a clean crankshaft position sensor signal (CKP) a clean camshaft position sensor signal (CMP) and a crank signal from the ignition switch.
If the PCM sees there three signals and it has power and GOOD ground and it actually is not the problem itself, the output signal to the ignition coils can be checked for signal from the PCM.
If the signal is good, test for power at the coils. If the signal is bad, swap PCM's with the other motor and see if it runs.
Unfortunately, there are no INTERNAL PCM tests you can do.
I believe on the 525, a relay supplies battery power to the ign coils. Check that relay for power and control circuits from the PCM accordingly. Does the relay work?
Its all basic diagnostic trouble shooting for a skilled tech. As long as it doesn't start "SOMETIMES", it shouldn't be that hard to find the answer.
In order to start and run, the PCM needs several things to happen and then it either responds or it doesn't.
Step one is to verify when the ignition key is turned to the ON position, does the fuel pump come on for approx 2 seconds to prime the system. If so, the PCM is getting ignition voltage, the FP relay and FP both work. If not, either the PCM remains un powered, has very poor ground, the relay is unpowerd or ungrounded by the PCM or it relay is ng or the pump is NG. Just need to follow back from the pump to see where the power stiops and fix the issue.
For igniton to occur, the PCM needs to see a clean crankshaft position sensor signal (CKP) a clean camshaft position sensor signal (CMP) and a crank signal from the ignition switch.
If the PCM sees there three signals and it has power and GOOD ground and it actually is not the problem itself, the output signal to the ignition coils can be checked for signal from the PCM.
If the signal is good, test for power at the coils. If the signal is bad, swap PCM's with the other motor and see if it runs.
Unfortunately, there are no INTERNAL PCM tests you can do.
I believe on the 525, a relay supplies battery power to the ign coils. Check that relay for power and control circuits from the PCM accordingly. Does the relay work?
Its all basic diagnostic trouble shooting for a skilled tech. As long as it doesn't start "SOMETIMES", it shouldn't be that hard to find the answer.
09-27-2013, 05:21 AM
#12
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Location: Ponca City, OKlahoma
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I am have this exact problem
No fuel pump prime when key is turned to on position
And
No spark
I took my volt meter and confirmed power to the coil packs but there is no spark being produced out of the packs.
What turned out being the fix when you were having this same issue
And
Cab anyone give me a good place to start checking for issues so to possibly fix this problem
Thanks guys in advance for your help
No fuel pump prime when key is turned to on position
And
No spark
I took my volt meter and confirmed power to the coil packs but there is no spark being produced out of the packs.
What turned out being the fix when you were having this same issue
And
Cab anyone give me a good place to start checking for issues so to possibly fix this problem
Thanks guys in advance for your help
10-01-2013, 02:26 PM
#13
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Got to love modern EFI, it won't run, no spark and the computer tells you everything is fine. I can't wait until someone gets EFI worked out. It sure is not there yet.
10-01-2013, 02:33 PM
#14
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Location: Between A Womans Leggs in IL
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I am have this exact problem
No fuel pump prime when key is turned to on position
And
No spark
I took my volt meter and confirmed power to the coil packs but there is no spark being produced out of the packs.
What turned out being the fix when you were having this same issue
And
Cab anyone give me a good place to start checking for issues so to possibly fix this problem
Thanks guys in advance for your help
No fuel pump prime when key is turned to on position
And
No spark
I took my volt meter and confirmed power to the coil packs but there is no spark being produced out of the packs.
What turned out being the fix when you were having this same issue
And
Cab anyone give me a good place to start checking for issues so to possibly fix this problem
Thanks guys in advance for your help
