v70 electrical problems

jordanfiji · Post by **jordanfiji** » 12 Jul 2018, 15:16

My V70 2008 is giving the following symptoms for a few weeks now:
- hatch open warning
- rear baggage room light not working
- rear window wiper not working
- rear window heater not working
- auto door locks not working (autolocking after 5km/hr speed)

I've done the following:
- replaced the latch unit on the hatch
- checked the back light bulb
- checked continuity on the rear window heater
- checked the wires for frays everywhere I could think of
- checked all relevant fuses

What else could be the problem, what action could I take? Thanks!

Post by **mrbrian200** » 12 Jul 2018, 22:08

I believe the autolocks don't engage when it thinks a door, hatch, or the trunk (on a sedan) is open, so that's probably not technically a 'fault'.

The wire(s) running to the hatch may not appear obviously damaged or frayed to the eye. The copper conductor can break without damaging the insulation. I've had this happen twice over the years on various vehicles.
Both were at points where the wire was subject to flexing. Once in a door grommet, and another time on an engine harness where it jumped between the chassis to a sensor attached to the intake piping that flexed the wire a little each time the engine rocked under torque.

You have to trace the wires with a circuit tester. If you find a break, you will want to replace that section of wire with very fine stranded wire so that the repair/junctions to the original harness aren't in the area that gets flexed or it's likely to break again prematurely.

jordanfiji · Post by **jordanfiji** » 17 Jul 2018, 07:43

I have now tested all of the wires from the hatch to the main body of the vehicle and all were intact and gave good continuity. I didn't go from the back of the car up to the front, but I don't think that there would be any fatigue there.

Any other ideas what could be wrong here? I've also tried to "reset" the warning light by disconnecting the negative battery terminal, though I suspect this is not necessary / effective.

Post by **oragex** » 17 Jul 2018, 08:56

I'm thinking about the micro switches on the door latches or on the trunk. Try isolate the faulty part by pulling it's fuse if it has a separate fuse or try just unplugging the latches one by one (may require door panel removal)