Connect a jumper wire between the FPDM PWR (VPWR for Continental) pin and FP PWR pin at the FPDM harness connector.
Measure voltage between the FP PWR circuit at the fuel pump harness connector and the battery negative post.
Is voltage greater than 10.5 volts, AND within 0.5 volt of the reading in KB72?
KEY OFF. REMOVE jumper. VERIFY previous test steps. CHECK related connectors for corrosion, etc. If all checks are OK, REPLACE FPDM. KEY OFF. REMOVE jumper. CHECK for causes of high resistance in FP PWR circuit.
KB75 CHECK B+ TO ELECTRONIC ENGINE CONTROL (EC) POWER RELAY (CONTINENTAL), CCRM OR FPDM POWER SUPPLY RELAY
Disconnect CCRM (Escort, Mustang), electronic EC power relay (Continental) or FPDM power supply relay (all others).
Key on (to put same load on battery as previous steps).
For Escort, Mustang:
Measure voltage between pin 11 (B+) of the CCRM harness connector and the battery negative post.
Measure voltage between the B+ circuit at the electronic EC power relay harness connector and the battery negative post.
For all others:
Measure voltage between the B+ circuit at the FPDM power supply relay harness connector and the battery negative post.
Is voltage greater than 10.5 volts?
KEY OFF. GO to KB76. Improper voltage is being supplied to the CCRM, FPDM power supply relay or electronic EC power relay. CHECK associated wiring, connectors, etc. REPAIR as necessary.
Thursday, May 30th, 2013 AT 9:37 AM