Too Low

UB. Too low

UB1: Reading off diagnostic trouble codes (DTCs)
Read off diagnostic trouble codes (DTCs) from the engine control module (ECM) (LH 3.2/EZ 129K, Fenix 5.2, Motronic 4.3 or Motronic 4.4).
Was diagnostic trouble code (DTC) 1-3-2 (EFI-132) set?

Yes:
- UB2

No:
- UB3

UB2: Fault-tracing diagnostic trouble code (DTC) 1-3-2 (EF1-132)
Battery voltage is too low or was too low at some point in the past. Carry out fault-tracing for 1-3-2 (EF1-132.)
Then continue with:
- Operation done





UB3: Checking status
- Ignition OFF.
Select scrolling values.

Read off battery voltage.

Battery voltage should be more than 11 V.

If reading is OK:
- UB5

If reading is incorrect:
- UB4

UB4: Checking battery voltage
Carry out fault-tracing.

Then continue with:
- Operation done





UB5: Intermittent fault
Check the 4-pin connector A for contact resistance and oxidation in accordance with GGB6.

Check the 24/14 connector (engine compartment harness - left threshold plate harness) for contact resistance and oxidation in accordance with GGB6.

Check wiring between control module, position A:1 (green/red lead), and the battery positive terminal for intermittent open-circuit.

Then continue with:
- UB6

UB6: Fault-tracing information
For intermittent faults fault-tracing is not followed by a verification because the fault is not present at this moment.

Do you want to repeat fault-tracing?

Yes:
- UB1

No:
- Operation done