Hello, I inherited at 2008 H3 (160K miles) from my dad, and have been trying to sort out the various maintenance and electrical issues. The alternator was replaced about 6 months ago.

1. Drivers side headlight intermittently worked
2. TPMS tire sensors and warning message
3. Check engine light P1174
4. rear hatch door wont lock, I can hear the actuator click when the the doors are locked, but it doesn't actually lock.

I replaced the battery and terminals today, with a Duralast Gold and the heavy duty gold duralast terminal connectors. I thought this solved most of the problems - it solved problems #1, #2, #3. but not the hatch door.

However, when I took the battery core back and drove it around 20 miles or so. got to autozone, went in and returned to my H3. it wouldnt even turn over at all, no electric - no power. I then proceeded to adjust the negative terminal, it then started up and I got it back home.

I dont know if this problem is solved now, but wanted to get feedback on the next steps. does this seem like a grounding issue? what is recommended to test the ground, or inspect it?

thanks a lot

 

"does this seem like a grounding issue? what is recommended to test the ground, or inspect it?"
Personally, I would simply:
A. Disconnect the battery.
B. Disconnect the ground to the body.
C. Clean, file, grind the entire ground and then reconnect the ground cable.
D. Re-connect the battery. Negative always first.
Start the engine and see what has changed as far as the message lights.
This may also be the issue with the rear door not "latching"...the ground may be compromised.
Hope this helps.
Others may have a better way or more definitive replies, so read them all.

 

Green crusties in the interior of fuse box. Battery, cables, terminals, etc. C105 and C106 ground lugs corroded or breaking, broken.
just all guesses.

 

C105 and C106 are located behind the air box and next to the master cyc/abs unit.
Make absolutely certain that your sun roof (if applicable) has not been draining into your bcm on passenger side. Check trailer hitch wiring up underneath rear bumper area. It is tucked up near cross support area. Yes even without a hitch the wire can corrode short.

 

Not a fan of Duralast anything, because they don't. Since EVERTHING electrical in the H3 depends upon a rock solid consistent connection to the battery, I would not have scrimped there.

Perhaps stating the obvious, Neg and Pos Battery posts are different size and require one each of a Neg & Pos terminal connector. Maybe you just did not have the Neg side properly tightened and all the way on the post?

Easy stuff first. Lubricate the rear door lock with a quality lubricant (NOT WD-40) like Blaster Multi-Purpose Lube, see if it helps.

 

As for the rear lock; open the door, remove the inside panel, and watch the mechanism. You should be able to see what is malfunctioning.