When the headlights are turned on, the taillights do not turn on?

Hi,

I attached a pic of the wiring schematic related to the exterior lighting. When the headlamp or parking lamp switch is turned on, the lighting control module (LCM) receives a signal which then powers the parking lamps. See pic below.

Here is what we need to check. At the LCM, there is a red wire with a yellow tracer. That wire should have power with the light switch on. We need to check that. If that has power, then locate a solid brown wire. That is the power out to the parking lamps. We need to see if there is power out at that wire. If there is power in and not out, the LCM is likely faulty.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Also, check fuses 21 and 27 in the central junction box under the dash are good and have power to them.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Let me know what you find.

Take care,

Joe

See pic below.

Hi, I check there is power on both sides in and out. The LCM was recall for the headlights 3 years ago. Should I take it back to the Ford dealer?

Hi,

Yes, if there was a recall, it sounds like the same problem has returned. Contact them and ask first to see what they tell you.

Let me know.

Joe

Hi, I took my car to the dealer. They want to charge me $200.00 just to check it out. So, i found a LCM used on EBAY for $125.00. I can change it myself. Thank you for the formation.

Hi,

Thank you for the update. If you have a chance, could you let me know if that takes care of the issue? I'm interested in knowing.

Take care,

Joe