07 S80 V8

rtoomey641 · Post by **rtoomey641** » 14 Apr 2018, 16:30

I have S80 AWD noticed right turn signal flashing faster than normal found that the signal on side view mirror is working but front and rear are not bulbs ok occasional bulb failure message would this be CEM or turn signal stalk?

Post by **jimmy57** » 14 Apr 2018, 17:50

If the mirror is flashing then the command from SWM/Stalk switch is getting to CEM. That doesn't leaave CEM as the only cause. The CEM will shut down power to circuits with shorts and not necessarily blow a fuse on that car. Has the car been scanned for codes with a complete scan tool? OBD scan tools have a very narrow scope and do not get info on the rest of the car.
You might go to the turn signals on front and back and remove both bulbs and inspect for issues. Then put one bulb in and see if it blinks. If it does not then turn off ignition while you remove that bulb and then try the other only to see if it blinks. The key off period while swapping bulbs will let the system reset so it will power up again for the other bulb.
Is there a hitch and and wiring for trailer lights?

I know of no pattern failures for turn signals on P3 models so I'm tossing general fault tracing and listing the peculiarities of that line given it uses transistor switched signals with bulb monitoring integrated into the CEM circuit. Bulb monitoring done this way has become widespread on even simpler vehicles.

rtoomey641 · Post by **rtoomey641** » 14 Apr 2018, 18:09

I will inspect bulbs tomorrow as we are in middle of ice storm now will post results was thinking after more research short on front bulb socket or bad connection have appointment for scan at dealer but its $118 for diagnosis trying to save on cost. Thanks also no trailer wiring

rtoomey641 · Post by **rtoomey641** » 15 Apr 2018, 13:08

So upon further inspection the wires in headlight harness are pretty dry rotted and were touching put some electric tape on for now got working going to replace harness. Thanks for the help.

Post by **mrbrian200** » 15 Apr 2018, 13:37

Wire insulation dry rotting after only 10 years? Corrugated conduit sure, but the actual wire insulation? Does that seem unusual to anyone else? It does to me.