Door Lock Activation Blows Rear Fuse - V70

Post by **chrism** » 24 Apr 2011, 20:42

2003 V70 Non-Turbo Base Model, 152,000 Miles.

There is a fuse #8 in the rear cargo fuse panel that controls the rear door locks and fuel door Lock. Activating the door locks blows the fuse. Operating the fuel door lock release does NOT blow the fuse. I have not gotten into the rear doors yet to isolate whether the problem is in the LH or RH door. I'm assuming there are places to disconnect the harness once I'm inside the doors so that I can isolate each one individually and hopefully determine which one is shorting. I would really like to disconnect the harness before it enters the door at all if there's a place.

The rubber boots between the pillar and the door appear be in good condition on both port and starboard sides of the ship. Is there a "typical" thing that shorts out that I should look for?

BTW - it's a bummer when you can't open the fuel door to pour in some of that $3.68 gas.

Post by **precopster** » 25 Apr 2011, 06:26

If you can place a ohmeter across the unconnected terminals of a good lock solenoid and compare this to both rear locks you may find one of them has gone to a short (or close to it) instead of around 50-80ohms.

Another way is to place an ammeter between one of the wires leading to one of the terminals to measure current flow of the solenoid while it engages, but be quick as it switches on & off in an instant.

Or just have a supply of fuses handy and disconnect left then right solenoids until the fuse stops blowing.

Obviously you'll want to check for chafing of the loom leading to each solenoid.

Post by **chrism** » 25 Apr 2011, 10:01

Thanks for the info. I'm hoping to find a chafed/shorted wire vs a bad solenoid. Do you know if it's common for those solenoids to go bad? I was hoping to find a place to probe the wires without taking the door panels off, but it's not really that big of a deal.

The resistance value of a good solenoid should help me pin down the problem.

jda2000 · Post by **jda2000** » 26 Apr 2011, 12:35

Chris, there are a whole bunch of relays in the REM that control different functions. Is possible that one relay is faulty and blowing the fuse.

Remove relay RM1, that one controls locking Left rear door. If fuse blows again after you activate the door locks, then that is not the culprit. Replace the relay back to its place.

Remove relay RM24, that controls locking right rear door. Try activating door locks and see if fuse blows.
Next try removing RM20, that controls rear hatch door locking.

By the way, the numbering of the relays is under each relay. Post back results.

Post by **chrism** » 27 Apr 2011, 14:57

Ah-ha! This is what I needed to know. Even if the problem is inside a door rather than the relay itself, I can isolate each door by pulling it's respective relay rather than going through the effort of removing door panels to buzz the wires out.

If I suspect the problem might be one of the relays, I assume the relays are identical so that I can swap them around to see if the fuse-blowing follows a certain relay vs a certain door.

It's just a shame I have to pull the relay to read the position number. Maybe Haynes has a reliable map??? Oh well, that's not not a big deal. It's probably a good idea to pull a relay and re-insert it every few years anyway, to scrape the dirt/corrosion from the contacts.

Thanks.

Post by **chrism** » 29 Apr 2011, 09:14

Whoever sells fuses loves me about now….

Here’s what I’ve learned so far:

My car has identical relays in RMI slots 15, 17, 18, 19, 20, 21, and 23. If I pull the relay from the RMI-20 slot I stop blowing fuses, but neither rear doors will lock/unlock as commanded. Also, when the relay is removed, activating the lock button on the driver’s door triggers the gas door, and pushing the gas door button triggers the rear door locks – the rear door lock buttons will actually go up and down when this happens. If I re-insert RMI-20, it only blows a fuse during “LOCK” action, not “UNLOCK”, but neither rear door locks will move in either action. Also, the fuse will blow during “LOCK” action regardless of whether I use the key fob or push down on either door’s manual button.

The rear hatch locks/unlocks properly without blowing a fuse.

Any ideas?

jda2000 · Post by **jda2000** » 29 Apr 2011, 12:55

Since #20 controls locking function of the tailgate, and removing it stops blowing the fuse but causes misbehavior in other electronics, I suspect a short in the wiring at the tailgate hinge, or the tailgate latch itself shorting.

Post by **chrism** » 29 Apr 2011, 13:41

The tail gate lock functions properly even with RMI-20 removed. Sorry if I didn't explain it well. 20 doesn't seem to affect the tail gate at all.

jda2000 · Post by **jda2000** » 29 Apr 2011, 18:15

chrism wrote:
My car has identical relays in RMI slots 15, 17, 18, 19, 20, 21, and 23.
Any ideas?

Chris, did you buy the car new or used. I wonder if somebody has been messing around with the REM relays.

There shoud be a relay in #22=fuel filler locking and also in #24=locking R rear door.

I confirmed that I have those relays in my '01 V70.

Post by **chrism** » 29 Apr 2011, 21:53

My V70 is a 2003. Everything was working fine until a few days ago, with the relays plugged into the sockets I've noted.