PCM problem
03-14-2005, 07:49 AM
#1
PCM problem I powered up the PCM in my '98 LS1 (in an 89 RX7) this weekend for the first time. I had a voltmeter on the fuel pump control output (conn. C2 pin 37). When I turned the key to "run" the pump control went to 12 volts and stayed there instead of going back to ground after ~2 seconds as it should with the 50 Hz fuel enable pin open.
I connected a 560 ohm resistor to it from ground and the pin went to zero volts, the pin acts like an input- it won't supply any current. I double checked all power and ground connections, the PCM ignition feed and the fuel pump control connection. Even if the PCM were fried the 12 volts on the pump control pin should have supplied enough current to operate the pump relay. Don't have a scanner yet so I can't tell the condition of the PCM.
The PCM came from a wrecked 98 Camaro so it must have been working when it wrecked!!
Anyone have any idea what the problem might be??
I connected a 560 ohm resistor to it from ground and the pin went to zero volts, the pin acts like an input- it won't supply any current. I double checked all power and ground connections, the PCM ignition feed and the fuel pump control connection. Even if the PCM were fried the 12 volts on the pump control pin should have supplied enough current to operate the pump relay. Don't have a scanner yet so I can't tell the condition of the PCM.
The PCM came from a wrecked 98 Camaro so it must have been working when it wrecked!!
Anyone have any idea what the problem might be??
