Freightliner M2 led headlamps water ingress

Applicable Vehicles

M2 106-112  with LED Headlamps

Symptoms

LED Headlamp Failures caused by water / moisture ingress

Issue

Most of the LED Headlamp failures are due to water/moisture ingress. The root cause was identified during inspection and testing of returned failed parts. The connector seal of the Turn - Parking Lamp part of the HARN-LT TRN,OL,CHAS was not installed at the production line (usually cause low mileage  failures) or after the Turn/Parking Lamp Bulb was replaced in the field. Figure 1 shows the Connector w/seal installed and the Headlamp Housing showing signs of contamination/debris.

This is an indication  that the Connector Seal was missing, allowing water to enter into the Headlamp Assembly and causing its failure. This conclusion was also validated via a submersion testing.

Solution

When replacing the LED Headlamp Assembly or for preventive inspection, check the Turn/Parking Lamp  3-Cav  Connector ( shown in Figure 2) and verify the Seal connector is present. If connector seal shown in Figure 1 is not present, replace connector assembly 23-13142-301 , with new connector that must include  the seal. 

Figure 2 shows the location of the 3-Cav Sealed Connector.