Control Unit Input Test

NOTE: For additional circuit information, see Fig 1 .

NOTE: Check the No. 2 (15 A) fuse in the under-dash fuse/relay box before testing.

Disconnect the 5-pin connector from the control unit. Inspect the connector terminals to be sure they are all making good contact. If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system. If the terminals look OK, make the following input tests at the connector. See CONTROL UNIT INPUT TESTS .

CONTROL UNIT INPUT TESTS

Wire

Test: Desired Result

Possible Cause Of Fault

BLK ⁽¹⁾

Check for continuity to ground: There should be continuity.

Poor ground. An open in the wire.

BLK/YEL ⁽²⁾

Check for voltage to ground: There should be battery voltage.

An open in the wire.

GRN/WHT ⁽²⁾

Check for voltage to ground: There should be battery voltage.

Faulty solenoid valve. An open or short in the wire.

BLU ⁽³⁾

Check for voltage to ground: There should be battery voltage.

Faulty ignition system. An open or short in the wire.

⁽¹⁾	Under all conditions.

⁽²⁾	With ignition switch ON.

⁽³⁾	When starting the engine.

If any test indicates a problem, find and correct the cause, then recheck the system. If all input tests prove OK, replace control unit.

Fig 1: Engine Mount Control System Schematic

Courtesy of AMERICAN HONDA MOTOR CO., INC.