Hello all. My low beams went out on me one freezing cold morning and I haven't been able to figure it out. All the other lights work. I replaced combination switch and have checked all fuses and relays which seem to work. I did run a test light and noticed I'm not getting power to fuses in the little fuses compartment in front of the battery (drivers side). Could it be a bad ground wire? Does anyone have a wiring diagram for the headlights? Does the integration relay have anything to do with the function of the low beams?

 

Can you post a photo of the fuse box in question?

Does the car have daytime running lights (DRL) and or auto off lights? Here the integration relay involvement and ground wire layout plays into all headlight circuit designs but greatly varies in complexity with the light system such as having normal lights,DRL and auto off.

Do the high beams work?

 

Yes car has DRL and also has auto headlights. High beams work with no issue. After further testing I found that I'm getting power to all fuses but not getting any power at the headlight socket for low beams. Attached pictures of what fuses boxes I've been looking at.

 

The photo of the relay/fuse box with 3 relays has the DIM, DRL No 4 and A/F HTR relays. Here make sure the DIM and DRL No 4 relay are working. On the off chance of failure check the 5A DRL No 2 and 10A HL-P LH and RH fuses. The fuses are in the same box as the relays. The DIM relay is farthest for the fuse area in the box and the A/F relay is closest. When the low beams are selected check the headlight bulb socket to determine if the low beams are getting power. When the low beams are selected, check that the negative terminal (ground terminal) on the socket is also grounded.

The DRL system works by having the DRL Relay operate to cut a resistor into the grounding circuit of the highlight bulb to lower the bulb voltage and output. The relay operation is controlled by DRL Relay Module which is solid state.

The combination switch on the steering column works by completing a ground circuit to whatever lighting is selected. In these cases a relay circuit is grounded to activate a relay.

The switch is not there to actually route power directly to a circuit as say an on/off on a light bulb in a house. The switch grounds a circuit to activate a relay which routes power to the headlight and or a relay that routes the negative terminal through the DRL resistor or directly to ground.

The DIM relay changes 12v power between the high and low bulb. The DIM relay may be a problem.

The DRL No 2 relay is what cuts in the DRL resistor or routes the negative terminal of bulb to ground. This relay could have a problem.

If you need low beams NOW you can remove the DRL relay and jump the No 1 and No 2 terminals of the socket. No 2 terminals is grounded to chassis. No 1 goes to the negative terminal of the headlight bulb.

See private message sent to you.