Intermittent electrical power failure on H1

Reply Subscribe

Thread Tools

Search this Thread

12-30-2018, 07:41 PM

VTM111

Junior Member

Thread Starter

Join Date: Dec 2018

Posts: 3

Intermittent electrical power failure on H1

I purchased a 1998 Hummer H1 over the summer, 6.5T and in the past month have had intermittent electrical power failure. There is no power at all to even start it up, and then 15 minutes later the power will just come on with no problem. Happens when engine is hot or cold and then it works perfectly not long after. Once it’s running it’s fine, haven’t had power failure while driving. I changed the battery and checked all connections, any idea on what it could be?

01-03-2019, 10:12 AM

pwlahaye

Junior Member

Join Date: Sep 2013

Posts: 7

Sounds like typical PMD(FSD) failure. I assume your truck has the PMD in the original location?

01-03-2019, 06:47 PM

VTM111

Junior Member

Thread Starter

Join Date: Dec 2018

Posts: 3

Quote:

Originally Posted by pwlahaye

Sounds like typical PMD(FSD) failure. I assume your truck has the PMD in the original location?

To be honest I’m not even sure. I will look more into that over the weekend, thanks!

01-08-2019, 01:59 AM

Chris Fisher

Junior Member

Join Date: Jan 2018

Posts: 18

I just added multiple grounds on my Hummer, the stock ground on the aluminum frame can get very corroded and was causing major electrical problems.

Everything is mint now!

01-08-2019, 07:16 AM

VTM111

Junior Member

Thread Starter

Join Date: Dec 2018

Posts: 3

Quote:

Originally Posted by Chris Fisher

I just added multiple grounds on my Hummer, the stock ground on the aluminum frame can get very corroded and was causing major electrical problems.

Everything is mint now!

Thanks for the info! Can you give me an approximate location of ground on the frame so I can look and see if that’s the case? Hummers are all new to me lol

01-08-2019, 11:54 AM

pwlahaye

Junior Member

Join Date: Sep 2013

Posts: 7

Quote:

Originally Posted by VTM111

Thanks for the info! Can you give me an approximate location of ground on the frame so I can look and see if that’s the case? Hummers are all new to me lol

Drift on over to The Hummer Network and read the first post on advice for new owners as well as the other Hummer forums. When you have troubles, like your electrical problem, check the most obvious things first. In your case, that would be the PMD. You might as well get a spare and mount it in a better position. All PMDs fail in the stock position due to heat. Hope you like cranking wrenches. Hummers are maintenance hogs and require a lot of attention but the several Hummer forums will have answers for any problem you might come up with and we are lucky to have several very good vendors for parts and information.