Symptoms

- Engine Light ON (or Service Engine Soon Warning Light)

Possible Causes

- Exhaust Valve Timing Control Magnet Retarder harness is open or shorted - Exhaust Valve Timing Control Magnet Retarder poor electrical circuit connector - Faulty Exhaust Valve Timing Control Magnet Retarder

When Detected

An improper voltage is sent to the Engine Control Module (ECM) through exhaust valve timing control magnet retarder.

Description

Exhaust valve timing control magnet retarder controls the shut/open timing of the exhaust valve by ON/OFF pulse duty signals sent from the Engine Control Module (ECM). The longer pulse width retards valve angle. The shorter pulse width advances valve angle.