Diagnostic Aids

Solenoid coil resistance must measure more than 20 ohms. Less resistance will cause early failure of the ECM "DRIVER". Using an ohmmeter, check solenoid coil resistance of all ECM-controlled solenoids and relays before replacing ECM. Replace any solenoid or relay that measures less than 20 ohms resistance.

Fig 1: TCC Electrical Diagnosis - Computer Command Control (4.3L, 5.0L & 5.7L Under 8500 GVW)

Fig 2: TCC Electrical Diagnosis - Computer Command Control (4.3L, 5.0L & 5.7L Under 8500 GVW)