Back to electronic woes
"headlight malfunction" warning came back while driving on the rain yesterday.
If 2 + 2 still equals 4 water got inside the headlight and burned the shit out of the module.
luckily I removed the module today from behind the wheel well cover and it's dry, but everything else in there is wet.
turns out the driver wheel well has a crack from the accident. I flinstoned it with hot glue temporarely but it came apart. it's basically showering the entire back of the headlight with water.
after some drying for about an hour
ISTA still reads "LIN bus malfunction" "check connectivity between FRM and STML and STMR
I am also seeing 12 v to the STML on the power side, so the only fault is the LIN bus cable from STML to FRM
the connector to the headlight is one that I did not get to last time wit the silicone, it was covered in water as long as all the other cables and connectors in that area.
Here is the fault cause analysis.
1. driver wheel well crack let water in
2. one or more connectors shorted out
3. since both headlight modules show a no communication error its fair to assume the FRM is toast again.
Remedy:
1 new fender on it's way,
2 spray all cables with "flex seal" it's a rubbery spray compound that somewhat seals after a bunch of coats.
3. Get new frm module.
Additional thoughts:
the reason every F10 coming out of the factory has headlight fogging is that the poorly designed wheel well shroud leaks water into the bumper area, this eventually evaporates and gets absorbed into the headlight trough the rear vents.
will figure out a way to reinforce the wheel well shroud, possibly spray the underside with flex seal until it's water tight.