H2 hummer dash gauge/went out ,then worked

[Monk]

Ok ,I haven't looked yet as wife just told me and she's at the store.

But apparently she started her h2 hummer and ALL dash function didn't work, even her radio didn't work,

It started, she drove a block shut it off then back on and all gauges ,light ,radio all was normal,

Even the tc/abs light that WAS on (few weeks) is now off, we knew about the abs sensor, but what would the possibilities be for that to happen? Battery ground?

[Roy]

We will let Kev answer this one, but it could be a simple ignition switch.

[Monk]

Tc/abs is back in dash, now the door lock light on dash was on. Just weird how works then don't work,

Also just now I turn on engine and for a sec , for a brief sec it sec battery no charging, but shows 14volts on gauge and in accessory mode (engine off) shows 12v ,I'd think alternator is charging, just seems weird

[whitehumh2]

OK, you need to check all your grounds!

As well, I think you might have a bad cell in your battery. But before you do anything with the battery start with checking all the grounds especially those Under the dash!

Also check your alternator for AC voltage leakage. Anything more than 200mV AC from the alternator and you can have a host of free game electrical issues!

[Monk]

Figured up date you's'

Ok we took to a garage today, on the way to the garage ,the door locks wouldn't work,seat heater stopped ,gas/oil/battery light was on, didn't show the line under drive or revese,, was so weird,her lights looked dim to me as she was following me to garage.

My wife called me saying the h2 has few computers and one won't read, it's the causing all the issues,

They said they can replace but can't flash, so said to take it to a gm dealer and get them to change that computer and then reflash so we can drive away.

I'm heading to the garage in hour to pickup and will know more, before heading to a gm.

[whitehumh2]

Ok keep us posted! But I still think it is a ground! Unless there is corrosion on the computer case causing a grounding problem.

[whitehumh2]

It can only be the BCM if it is a controller

[Monk]

Ok figured I should up date you's ,

Truck went to dealership and they diagnosed bcm was not responding, and changed it!

Wipers/door locks/seat heater/ and all gauges (basically almost everything) started to work

Only thing was our tc light was still on, my wife reports to me she felt her brake peddle ( was an older problem we just ignored) kick up hard a few times, she swore something was "weird " .

Sooooo again back to dealer and they diagnosed /replaced EBCM and now no more lights or kicks, and man that ebcm was pricey

So glad all due now,,