I have a 1990 240 and had a problem with the left (driver's side) turn signal. I checked the wiring, rewired some things that needed it, and replaced every single relay and switch in the circuit and it still did not fix the issue.

Yesterday evening, I was hunting down wires again and I finally saw a brief glimpse of copper when I passed over one of the tiny holes in the strut tower. I discovered a mouse (or something) seems to have chewed through the headlight wiring harness underneath the strut tower. I am trying to come up with options for this repair. If ANYONE has any great ideas (or an extra harness), please let me know.

I have had good luck keeping rodents out of my cars with cheap fabric softener sheets or go for the real McCoy "Bounce" fabric softener.

I know what's involved.

Last March I tracked a lack of tach display to the white/red wire in that harness under the strut tower. In order to repair the chewed wire I needed to pull the harness back toward the firewall. This one goes all the way to include the horn wires. I could not finagle the end past the left headlamp without removing the bucket.

In the past I've been able to use a cutoff wheel on a Dremel to get through the rust and replace the bolts with stainless, but in this case the lamp's adjuster plastic parts were broken before I even started.



Gave me an excuse to buy a set of aftermarket lamps. New lamps really improve the looks of the car, an 89.



You might try a little harder than I did to avoid pulling the horn wire through; I just hate to cut and splice a wire in that corrosion-prone area of the car.
--
Art Benstein near Baltimore

Why are a wise man and a wise guy opposites?

Go here:
https://www.davebarton.com/

Leave some bait packs in your engine bay,
and/or adopt a hungry barn cat.

Good luck, Bill