Sprinter Voyager Mirror Monitor VOM74MM Not Working

This document provides troubleshooting steps for the Sprinter Voyager Mirror Monitor VOM74MM when it is not functioning correctly. The primary focus is on issues related to connections under the driver's seat.

Under Driver Seat Troubleshooting

1. Ensure the two white 3-pin connectors are plugged together.
2. These two connectors are shown plugged together.
   • Connector "1" has red, white, pink wires (From PSM).
   • Connector "2" has red and black wires (powers to monitor).
   • NOTE: The harness with blue, black, red wires should be out of the circuit.
3. Verify that the connections into the PSM (Power Supply Module) are seated properly. The PSM harness supplies power to the Monitor/Camera system. The UTM harness part number should be 1651780 (if the harness label indicates 16517641, it should have been replaced with 1651780). Some Sprinters required this harness to be re-seated into the PSM.
4. Check that 25 AMP Fuses 14 and 15 are present and functional. These are located in the driver's seat fuse block.
5. Confirm that there is 12V DC power on the Pink and White wires of connector 1 (as shown in the diagrams) when the vehicle key is in the accessory or running position.
6. If 12V DC is present at the connector described in step 5, the issue might be with the connection directly to the monitor above the dome light, or the monitor itself could be defective.

NOTE: If the monitor has power, the indicator light to the left of the power button should be Blue when powered ON or Red when powered and in standby mode.

7. A potential final issue is that the PSM has lost its programming. This requires reprogramming by a Mercedes Dealer.

Troubleshooting Notes for Monitor Power

If the monitor powers up and the indicator light to the left of the power button is blue, then the camera in the rear of the van should be inspected for damage, or the connection to the camera in the headliner may need to be reseated.

Extra Notes and Pictures: Fix Kit in the circuit under the seat

The following describes the components related to a fix kit under the seat:

1. Connector from PSM (Power Supply Module)
2. Connector going to the monitor
3. Connector to field fix kit (remove)
4. Connector from Field fix kit (remove)
5. Field Fix Kit Harness black box (part of the harness that should be removed)

Important Connection: Connectors 1 and 2 should be plugged together. Connector 3, shown plugged into itself, is irrelevant if it is not connected to 1 and 2.