2010 Mercedes Benz C 300 (204.054) V6-3.0L (272.947) Page 188

1.3.2.1.5. No further information available.

1.3.2.1.6. Check power supply at control unit A1 (Instrument cluster).

1.3.2.1.6. No further information available.

1.3.2.1.7. Check power supply at control unit N80 (Steering column module).

Test 1.3.2.1.7.1: Inspect control unit N80 (Steering column module) for undervoltage fault.

Test 1.3.2.1.7.2: Test voltage supply of circuit 30 by means of actual value.

Test 1.3.2.1.7.3: Test voltage supply of circuit 30 by means of measured value.

Test 1.3.2.1.7.4: Interior CAN check

Test 1.3.2.1.7.5: Check the CAN communication with control unit CGW.

Test 1.3.2.1.7.6: Engine compartment CAN test

1.3.2.1.7.1. Inspect control unit N80 (Steering column module) for undervoltage fault.

If the fault code is not current, it may be deleted. In this case, the battery voltage was too low over an extended period.Charge the battery, if

necessary.Question:Is the fault current in several control modules?Note:This fault could result in consequential faults. You should therefore process

this fault first and then erase the fault memory.

YES

Possible cause and remedy

- Battery voltage too low.Test battery.Charge battery, replace if necessary.

- If fault occurs again:Check alternator.Communication with ECU required

- The quiescent current is too high.Test quiescent current.

NO

Manual check of supply voltage

Test prerequisite

- Fuse F34f33 (Fuse 33) in component F34 (Interior fuse box) is o.k.

- Actual value is not okay or there is a complaint.

Status of relevant actual value:

- Voltage at terminal 30:Warning! Communication with ECU required.

Test sequence

- Switch off ignition.

- Remove component Airbag.

- Please refer to WIS document AR91.60-P-0660.

- Remove component Multifunction steering wheel.

- Please refer to WIS document AR46.10-P-0100.

- Remove component A45 (Clock spring contact).

- Please refer to WIS document AR46.10-P-0200.

- This information can be shown using the help function (F6 button) in menu item 'Testing and repair work'.

- Measure direct voltage with multimeter between sockets [N80] 1.8 and [N80] 1.9

Specified value

- Voltage [11.0...14.5] V

Question

- Is the measurement value OK?