Vehicle Does Not Lower At 55 Mph
- Inspect for defective speed sensor, control unit or wire harness. With vehicle stopped, operate height control switch to verify indicator light operates. If light is off, check for ground between indicator light and control unit. Repair wire harness and recheck system.
- If light is on, test speeometer pulse input at control unit terminal No. 22. To perform this test, apply voltmeter positive lead to control unit terminal No. 22 and negative lead to ground.
- Move vehicle 7-10 ft. (2-3 m). Count each 0-12 volt oscillation of the voltmeter as a pulse. If approximately 5 pulses are read, replace control unit. If not, repair vehicle speed sensor wire circuit or replace speed sensor.