BCM?

[giant h2]

Battery has been good for months now! A few days ago the 2005 H2 (150000 miles) had a weird chime with no dash lights or alerts. Yesterday she started normally but when I shut her off the red battery light dash icon stayed on with the key off and out.

Also when I opened the door the radio stayed on and played delayed power didn't go out. It has never done that before? I had to shut the radio with the on/off vol. button (nav radio) it went off normally but I could hear a hiss noise like radio static? Key was out of ignition.

Later on I drove her and all was good but same happened at shut down. Battery symbol light on and radio played with key out and door open and hiss noise.

This morning the H2 was dead and needed a jump start. Any suggestions welcome?? Please help?

notes since last battery issue I disconnected the onstar with fuse removal and pulled out the nav disc.

[fyr145]

My guess is the alternator is not charging the battery. Test alternator for output amperage. Charge battery first.

[giant h2]

Originally Posted by fyr145

My guess is the alternator is not charging the battery. Test alternator for output amperage. Charge battery first.

it was tested with replaced (new) battery in January and was fine. Also it charges the battery after driving around for a bit.

[giant h2]

New Data: If I pull the SEO ACCY fuse with the Engine off key out (which has a wire from the back up cam wrapped around it) and re-seat the fuse the battery light icon on dash goes out, the PRNDL goes out and the radio goes off. Start the car and turn it off and all hell breaks loose again?

Thought it could be the ignition switch? So I wiggled the key and no joy. Interesting, if I touch the rear wiper sw or the windshield wiper sw with the door closed the battery icon goes out and the retained assy power plays the radio and dash cluster lights until door opens. If I have the door open and touch either wiper sw, all power goes off with key out. What does all this mean?

[HUMTECH]

Did you remove the back up cam wire or leave it in place when you reinstalled the fuse? If something is wrong with the camera it could power that circuit which is tied directly to the TBC ACCY fuse which in turn can be powering up the bcm

[HUMTECH]

If you did remove it and problem is still there. Remove rear wiper fuse and test system. If its still a problem remove ws wiper fuse and check it. Both those circuits run off the same power bus in the ip fuse panel so anyone of them could cause an electrical backfeed

[giant h2]

Originally Posted by HUMTECH

If you did remove it and problem is still there. Remove rear wiper fuse and test system. If its still a problem remove ws wiper fuse and check it. Both those circuits run off the same power bus in the ip fuse panel so anyone of them could cause an electrical backfeed

I removed the back up cam wire and the prob was still there with or without it. I did not mess with wiper fuses. I only tried the wiper switches to see if the ignition may have thought it was in the assy power position with the key out. I did notice that when I jump started the dead truck this morning, as soon as the engine started the WS wipers cycled once? Did not think anything of it at the time.

What can this be????

[HUMTECH]

remove the wiper fuse and see if problem goes away, if it does may have a bad wiper module backfeeding the circuit or a bad switch

[giant h2]

Originally Posted by HUMTECH

remove the wiper fuse and see if problem goes away, if it does may have a bad wiper module backfeeding the circuit or a bad switch

will do tomorrow, wiper module is new within the last 6mos, old one got wet.

[giant h2]

Originally Posted by HUMTECH

remove the wiper fuse and see if problem goes away, if it does may have a bad wiper module backfeeding the circuit or a bad switch

I pulled rr wiper fuse 10a and nothing. Pulled Ws wiper fuse 25a and everything went off as it should with the door open and key out. Not sure what that means? Also as before if I touch either wiper sw (rear or WS) everything resets as well. In fact any wiper function including hitting wash on either resets the electrical system. Data: I installed a new wiper module around Nov last year and even wrapped it in a latex glove to keep the water out.

[HUMTECH]

Next i would reinstall all fuses and disconnect the wiper motor connector. If all is good at that point problem is in wiper motor

[HUMTECH]

Also wrapping module in latex is prob not a good idea, will still get some moisture in it due to heating up and cooling down creating condensation. With it wrapped up there is no where for the condensation to get out

[giant h2]

Originally Posted by HUMTECH

Also wrapping module in latex is prob not a good idea, will still get some moisture in it due to heating up and cooling down creating condensation. With it wrapped up there is no where for the condensation to get out

Looks like its the ignition switch? Sprayed some WD 40 on the cylinder and then went over to a friend for scan. Of course when I got there everything worked fine! My master tech buddy scanned the computer and the BCM stored codes read power mismatch. After I left stopped for gas and shut the car off pulled out the key opened the door and got out and there it was again dash lit up and radio on. Put the key back in and wiggled it and power went off, so what do ya think?

[HUMTECH]

Could be. If the BCM is getting a backfeed from somewhere it can also set that code as the BCM is the power mode master. I would leave the wiper fuse out for awhile and see if it acts up with it out. Seems odd that it quit with it out before now all of a sudden you wiggle the lock cylinder and its changed it. Also try putting the key just halfway in ignition cylinder and lightly try to rotate it forward, if battery light comes on ignition switch could be out of adjustment(they are adjustable)

[giant h2]

Originally Posted by HUMTECH

Could be. If the BCM is getting a backfeed from somewhere it can also set that code as the BCM is the power mode master. I would leave the wiper fuse out for awhile and see if it acts up with it out. Seems odd that it quit with it out before now all of a sudden you wiggle the lock cylinder and its changed it. Also try putting the key just halfway in ignition cylinder and lightly try to rotate it forward, if battery light comes on ignition switch could be out of adjustment(they are adjustable)

Left the fuse out all day, no issues! Put it in after lunch and there goes trouble! Do you think that the 6 month old WCM (wiper control module) could be bad already? Did these have quality issues? I am confused. And why did a key wiggle fix it on one occasion? Oy

[giant h2]

Took off the cowl to expose my least favorite part, the WCM (wiper control module) cover. When I removed the small harness, nothing changed. When I removed the larger harness the power mode reset to key out and everything went dark as its supposed to. Once again Humtech was right on! Also, when I plugged the wire harness into the wiper cover, and tapped on the back the power also reset to normal, I find that very weird because there are no moving parts just a circuit board?

Last question since I bought this part in October from GM parts direct will AC Delco warranty it?

[HUMTECH]

Not sure on the warranty. If you closly inspect the circuit board you may notice cold solder joints. May see very fine cracks around base of a solder joint. You can try to heat any of these up with a soldering iron and retry it in truck. I used to fix the old chevy pulse boards sometimes this way.

[giant h2]

Originally Posted by HUMTECH

Not sure on the warranty. If you closly inspect the circuit board you may notice cold solder joints. May see very fine cracks around base of a solder joint. You can try to heat any of these up with a soldering iron and retry it in truck. I used to fix the old chevy pulse boards sometimes this way.

Thanks for all the help I appreciate your knowledge!

[Contract_Pilot]

HUMTECH is smart.

[giant h2]

Originally Posted by Contract_Pilot

HUMTECH is smart.

Humtech is awesome!

On a side note as you can see from the weather channel, Florida is getting drenched. Guess what my new less than 1 month old module is acting up again with intermittent wiper control issues. Does anyone know if this was solved on the 2008/09 models?