I usually lurk the finnish volvo forums, but my V70 2.5T 2006 has been infected with electrical gremlings so badly that I decides to try reaching a more international audience in hopes of finding some help.
The issue:
Intermitten indicator failure, but only to the right. Sometimes it just works, sometimes it acts as if it has a faulty connection somewhere as it turns the indicator on and off erratically and without a steady “rythm” and sometimes it’s just completely dead.
While the fault is present, either the intermitten erratic blinking or completely dead, the reset button on the stalk also stops working, but hazard lights function normally, same for the arming of the alarm where the indicators blink to confirm locking/unlocking.
No codes in VIDA.
Things tried:
Testing with known good indicator stalk, no change.
Removing SWM and resoldering all pins + bending the pins in the stalk connector to ensure good connection. No change.
General cleaning of all connections.
Other small things I’ve noticed:
When the fault is active, the indicators will work normally if I pull the stalk towards me to the point where the high beams go into “flash” mode but will not work if I pull it far enough to actually turn on the high beams.
The fault is usually not active when I start the car in thr morning but will appear after just a few minutes of driving, this sounds to me like a pcb losing connection as it warms up.
I have a CFE in my OBD port with the comfort/lane change function enabled, so it blinks 3 times when I just flick the stalk and I’ve noticed that when the fault is in the erratic mode, flicking the stalk works normally and the CFE is able to turn the indicators on/off but when the fault is at its worst and the indicators are completely dead, the CFE will no longer work.
My current theory:
Faulty SWM or CEM, but leaning more towards SWM.
The fault seems to be a communication failure between the stalk and SWM, since the CEM is able to control the indicators when using hazard light and when locking/unlocking. It should not be a communication failure between SWM and CEM either, since they’re talking over CAN right? So it either has comms or not, not this kind of only one side indicators not working. Also since VIDA shows no codes, makes me assume that SWM – CEM communication is operational.
Any ideas or suggestions? A SWM replacement is not cheap and will cost more or less 10% of the cars total value.
Sorry for the wall of text, but I wanted to give as much relevant information as possible.