Checking the power supply and ground for the upper electronic module (UEM)
For further information about the fuse and terminal pin numbers, see appropriate wiring diagram article.
Check that the fuse in the fusebox in the passenger compartment for the upper electronic module (UEM) is intact.
If the fuse has blown, check the circuit after the fuse before replacing the fuse. Check for a short-circuit to ground.
Check the connectors and wiring for the upper electronic module (UEM) and the battery connection. Check for contact resistance and oxidation. Check for loose connections.
Check the cable between the control module and ground. Check for an open-circuit. Check for a short-circuit to supply voltage.
Remedy as necessary.
Other information:
- To access or replace the fuses, see Fusebox, passenger compartment, replacing
- To access or replace the upper electronic module (UEM), see Interior lighting and upper electronic module (UEM), replacing
- To connect the breakout box, see Connecting the breakout box
- For information about signals and connectors, see Signal specification
- For information about checking wiring and terminals see Checking wiring and terminals. Permanent fault .
Was a fault detected?
- YES
Refer to Checking the function of the upper electronic module (UEM)
- NO
Refer to Signal missing