Fiero L4-151 2.5L (1985)
-
CKT 335 and relay terminal "B" grounded
c.
A/C pressure control
-
A/C high side pressure above 260 to 310 psi (1792 to 2137 kPa).
-
A/C pressure switch closed to ground.
-
CKT 335 and relay terminal "B" grounded.
Solenoids and relays are turned "ON" or "OFF" by the ECM internal electronic switches called "drivers". Each driver is part of a group of four called
"Quad-Drivers". Failure of one can damage any other driver within the set.
Solenoid or relay coil resistance must measure more than 20 ohms. Less resistance will cause early failure of the ECM "DRIVER". Using an
ohmmeter, check the coil resistance of the following before installing a replacement ECM.
d.
A/C Relay, pins opposite harness connector terminals "A" and "C".
e.
Fan Relay, pins opposite harness connector terminals "B" and "C".
