1998 PCM - replaced - still not fixed?
#11
#12
#13
Yes that's a 5V supply from the PCM. It only goes to the transmission solenoid assembly but you have issues with the transmission too. One of the quirks with these PCMs is that if something shorts the sensor supply voltage anywhere it causes all sorts of different issues. I'd check sensor supplies, especially down at the transmission because quite a few people had problems with shorts inside the transmission.
#14
I managed to get my truck hooked up to a scan tool today. Wasn’t convinced it would do any good but no harm in more information.
This from the mechanic:
“Attempt to communicate with scan tool but PCM will not respond, other module responding except PCM.”
So same issue as the old PCM.
I’m strategizing my trouble shooting protocol for tomorrow; lots of wires to check. Thanks for the feedback.
This from the mechanic:
“Attempt to communicate with scan tool but PCM will not respond, other module responding except PCM.”
So same issue as the old PCM.
I’m strategizing my trouble shooting protocol for tomorrow; lots of wires to check. Thanks for the feedback.
#15
I managed to get my truck hooked up to a scan tool today. Wasn’t convinced it would do any good but no harm in more information.
This from the mechanic:
“Attempt to communicate with scan tool but PCM will not respond, other module responding except PCM.”
So same issue as the old PCM.
I’m strategizing my trouble shooting protocol for tomorrow; lots of wires to check. Thanks for the feedback.
This from the mechanic:
“Attempt to communicate with scan tool but PCM will not respond, other module responding except PCM.”
So same issue as the old PCM.
I’m strategizing my trouble shooting protocol for tomorrow; lots of wires to check. Thanks for the feedback.
#16
#17
I list all options because if the OP is like me the worse/rare thing that can happen will happen to me . I could be driving an all electric vehicle and still run out of gas
#20
I figured it out! The Engine Speed Sensor (RPM sensor) must be shorting out internally.
I started trouble shooting by unplugging each of the 5V sensors related to the PCM and seeing if fixed the problem. When I unplug the RPM Sensor, all of the gauges work except the speedometer.
The transmission isn’t working correctly but that seems to make sense as RPM’s and the transmission talk through the PCM.
Thank you everyone for pointing me in the right direction.
I started trouble shooting by unplugging each of the 5V sensors related to the PCM and seeing if fixed the problem. When I unplug the RPM Sensor, all of the gauges work except the speedometer.
The transmission isn’t working correctly but that seems to make sense as RPM’s and the transmission talk through the PCM.
Thank you everyone for pointing me in the right direction.