Hello Everyone

I am new this forum but not new to hummers My old man got him self a wagon type 1995 H1 we had it for like 6 years now. It been going well with no major problems but a oil hose melted when the exhaust doughnut (gasket) was no longer there we got that fix and a few weeks later we got a PCM light that have a gear ring over it had just came on, it is below the check engine light. I started to notice when I have the lever in 1rst gear at a dead stop and when I let go of the breaks it creeps forward and dose a jerk and speeds up a little at idle speed. It also dose that when I am steeping on the accelerator a little and it dose the same thing but harder jerk. It seems like it sift from 1rst to second but it did not causes once I reach 20mph I need to shift to second gear.

Be causes of that problem we were going to see if we can pull out the codes and fix the problem.... However I can not find the OBD location so I can jump the two terminals to pull the code. We search on the internet and I cant find it and they said that it under the dashboard and it a OBD2 but I cant find anything relating to that under the dash.
Where is the OBD terminal located in the engine area ? OR dose this 1995 hummer have an OBD2 ? it a Non turbo 6.5L diesel and since it not a turbo I do not think it NEEDs a OBD2 .... Any correction and insight on what I have in this beast and possible problems I am having will be appreciated!

Thank you

 

You have a mechanical diesel with a electronic 4l80E transmission. A.K.A you do not have a computer controlling your motor but you do have one controlling your transmission.

 

Thank you
That is what i figgure at least I dont have to wounder. The TCM light is on how can I check to see what kind of error it showing?

 

A 1995 is OBD 1. It will only monitor the transmission for that year truck with a NA engine. You need a Tech1 or equivalent to read the codes. It should have an OBD1 type connector. Sometime in late 1995 or early 1996, Hummers went through a transition where it had a OBD1 TCM with an OBD2 type connector. This connector is just below your left knee on the plastic kick panel unless moved by prior owners.
Gil

 

Sorry for late reply in the process of moving to a new room.
I will keep looking for any thing that resemble and OBD or DIG connection. Can I just jump two terminals that is usaly in the engine compartment like MOST 95 and older cars have ? That how I been pulling codes with out a reader cars above 96 I have my own OBDII reader hook up to my laptop.

ALSO update I said a PCM I think I ment TCM transmission control modaule.
We like to go to Mohab with this beast but want to make sure everything is in top shape

 

Here is how to get codes via blink method
Gil

 

My 95 H1 has a CEL. Smog guy won’t touch it

mine is petrol. Is the location same as diesel ?

 

I think the transmission module is under the engine cover. On the driver side, you plug into that.