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How To Use Circuit Tests

1) DO NOT  perform any CIRCUIT TEST unless specifically instructed by a procedure under SELF-TEST or SWITCH MONITOR TEST. Ensure all non-EEC related faults are corrected. FOLLOW EACH TEST STEP IN ORDER UNTIL FAULT IS FOUND. When more than one code is received, start with the first code displayed.

2)  CIRCUIT TESTS check electrical circuits to make sure they are okay before replacing sensors or any other components. Always test circuits for continuity between sensor and ECA. Test all circuits for short to power, opens, or short to ground.

3) DO NOT  connect any test light, or measure voltage or resistance at ECA unless specified in testing procedure. DO NOT  pierce wiring. If backprobing is specified, always backprobe harness side of connector; DO NOT  probe connector side.

4)  Isolate both ends of circuit and turn key off whenever checking for shorts or continuity, unless specified otherwise. Disconnect solenoids and switches before checking circuit continuity, or energizing solenoids.

NOTE: A short is defined as a resistance value of less than 5 ohms.
Fig 1: ECA Connector Terminal I.D. (Exc. 1.8L & 2.2L Non-Turbo MTX)
G91G08141Courtesy of FORD MOTOR CO.
Fig 2: ECA Connector Terminal I.D. (1.8L & 2.2L Non-Turbo MTX)
G91I08142Courtesy of FORD MOTOR CO.