Service Stab Stystem failed/ Reduced Power
 

I have a 2007 H3 Tactical edition. It is showing on the dash that i have a check engine light and a traction control light on. On the screen it says Service stab system failed/ Reduced power. Can anyone help me with this? Not sure if its a sensor or switch. The 4 wheel drive still locks in and comes back out.

have the codes read and let us know what they are.

Code said it was the throttle body. The machine could only read what the check engine light says. Would the throttle body be the issue for the traction control? Loss of power makes sense, but not the traction control.

Fixed it
 

It was the wiring that connects to the throttle body sensor. One of the wires were cut in half. Looks like a rat had chewed through it. Just spliced both ends of the cut wire, added an additional wire, then it was good to go. Runs back to normal.:D

i have the same problems loss of power,traction faliure, i already put new spark plugs, new thermostat, put new throttle body has been in the shop for a wk already the bill is getting higher now , so far the mechanic is asking $200 for the work he has put into it but still running a lil ruff he says. so dont knw what else to do, before i take it to a electrical mechanic, i was told to check here first. so can anyone please help thanks rosa

Problem fixed
 

I had the same issue with extreme reduced power. (Felt like the i5 engine was running only on 2 cylinders. Serious rough idle with a fair bit of a shake of the whole car) The problem occurred on heavy acceleration and sudden heavy breaking. Rough idle right after the heavy breaking. I've just cleaned the spark plugs with petrol and dried them and put'em back together in the same order. Be careful not to use a wire brush. Use a toothbrush for it. And watch out not to change the space of the plugs. Otherwise try putting new spark plugs. This is a trick my dad thought me. She runs like a dream again. Also it might pay to have an isolator switch installed at the front of the shell. When things go wrong, switch ur isolator off then back on. It restarts everything. That's how I survived the drive back home. And then the next morning I've done the clean up of the spark plugs and she's back to normal. Just to check it I've jack rabbited her with heavy acceleration (open trottle) and heavy breakin. She's back to normal. Mine's a h3 2007 3.7 lire 5 cyl. Thought I should let ya's know. Goodluck. May not be a good idea if ur truck is under warranty. But if it ain't, give it a try. It took me about an hour and a half. Hope this helps. :)

Welcome to HF. While I can appreciate your wanting to help, please STOP digging up OLD threads.
https://www.hummerforums.com/forum/n...bumping-23220/

You should also note that your problem is NOT even similar to what this thread is about. The thread was started relating to the DIC (Driver Information Center) message stating: Service stab system failed/ Reduced power. This thread is not about the OP's truck "feeling" sluggish, it is about the fault condition that triggers the message in the dash display.

Thank you for your cooperation.

Sorry for ur inconvenience.

That's the messege I got in me DIC. That's actually what I've Googled too. And I came up with this thread. On the top list of Google. While my solution was a simple one yet effective. I only wanted to help people with the same issue. If digging up an old thread is what it takes am happy to leave my post there. But if that ain't allowed, ADMINISTRATION, please delete my post. I give u full authority. Thanks. Once again I repeat, my sole intention was to help others with a very simple solution.

I tried using better petrol too. But it didn't fix the problem. Tried premium. Didn't work. When I pulled the plugs out I've noticed that the plugs had a fair bit of carbon build up. Cleaned'em dried'em and put'me back together and it's fine again. Sorry for any inconvenience caused. But that was the FIX for my problem. Hope this helps.

I have a 06 H3 and mine went to reduced power mode off and on for months. A battery disconnect and reconnect seemed to work for awhile until one day it didn't. Took it in and they replaced my throttle body. H3 ran smoother but it went back into Reduced power mode. On a whim I disconnected my Air Mass Sensor flow by the air filter and started it up. The dash still showed Reduced Power mode but the H3 ran like nothing was wrong. I ran some Mass Air Cleaner through the sensor and so far it is running good again but I am always worried now that Reduced power mode is gonna pop up at the worst time. Getting the PCM switched out tomorrow by the dealer but if you're in a bind try disconnecting the mass air flow sensor.