Trouble Code 48 (Solenoid Valve 1)
SOLENOID VALVE 1Explanation
The solenoid valve 1 is checked completely by the control unit during the initialization phase by briefly activating it. The following defects can be detected during operation dependent on the status of the solenoid valve:
- Active: Short to ground, plausibility (driver transistor defective)
- Passive: Short to positive. break
Effect of Defect
Mechanical emergency program.
Possible Cause
Wire or winding of solenoid valve 1 defective, or driver transistor detective.
Troubleshooting
Perform component activation. Measure signals. Ground is constantly applied at control unit Pin 54. When active, control unit switches positive (approx. battery voltage) to Pin 48.