No start condition, ATAP keeps disconnecting. Is there any way to test the PCM?
08-16-2011, 12:06 AM
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No start condition, ATAP keeps disconnecting. Is there any way to test the PCM? Hey guys, I'm trying to help a buddy with a 99 Z28 who can't get his car started. It does have good cranking speed though.
Service Vehicle light is on. Security light is off (it does work, as it's on during the instrument light test) And at one point (that I saw) the SES light flickered for a second or two.
At first he said the fuel pump was bad, because he wasn't getting any pressure (there is a gauge on the car).
While I was there, we discovered the fuel gauge wasn't reading.
After pulling the fuse/relay and switched them to make sure they were good. Which they were.
Used a test light to see if there was power to the relay, and there was power on the switched side, but when he cycled the key, none of the other terminals came up for the few sec it primes.
I thought the computer might not be sending a signal to the relay to turn on, so I had him jump it, and the pump ran fine. Good pressure.
After doing that, the pump will sometimes prime when the key is put in the on position. But even with pressure it won't start. The gas gauge will also read.
I tried to connect auto tap, and it will read the VIN, then go through the parameters, then disconnect.
I'm beginning to suspect the PCM may be toast, but I am hesitant to tell him to replace it without testing first. I have no clue how do that, or even if I can.
Any help would be appreciated.
Thanks in advance
Troy
Service Vehicle light is on. Security light is off (it does work, as it's on during the instrument light test) And at one point (that I saw) the SES light flickered for a second or two.
At first he said the fuel pump was bad, because he wasn't getting any pressure (there is a gauge on the car).
While I was there, we discovered the fuel gauge wasn't reading.
After pulling the fuse/relay and switched them to make sure they were good. Which they were.
Used a test light to see if there was power to the relay, and there was power on the switched side, but when he cycled the key, none of the other terminals came up for the few sec it primes.
I thought the computer might not be sending a signal to the relay to turn on, so I had him jump it, and the pump ran fine. Good pressure.
After doing that, the pump will sometimes prime when the key is put in the on position. But even with pressure it won't start. The gas gauge will also read.
I tried to connect auto tap, and it will read the VIN, then go through the parameters, then disconnect.
I'm beginning to suspect the PCM may be toast, but I am hesitant to tell him to replace it without testing first. I have no clue how do that, or even if I can.
Any help would be appreciated.
Thanks in advance
Troy
