Short circuit to ground or overload on proportional valve (PWM Output 5).
1. Check cable harness and connectors between ACSX (E752) and proportional valve (V542). 2. Check proportional valve by resistance reading. Should be approx. 7-8 ohm. Replace valve if resistance is close to 0 ohm.
What you'll see
Proportional valve is deactivated, output turned off on hardware. No damping is available on the left damper, since the valve is not controllable.
System reaction
Amber ACS warning lamp Speed Limitation
Diagnostic depth
None or too low resistance in circuit connecting to proportional valve.
- High-side wire (B16) connecting ACSX and proportional valve is short circuit to ground. - Defect connector in either ACSX or proportional valve. - Defect proportional valve (internal short-circuit).