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While we are at it, here is the plug pinout so you can get the proper color to the right pin. PDF also attached
OK I can now identify the wires coming from the throttle body all eight.
I'm now suspecting this orange w/ black tracer position B, may have been replaced w/ a grey from the throttle body. position B should be a orange w/ black tracer.
like all the other seven wires color codes match from TB to harness excerpt this orange/black. I will closely inspect position B. an report back
what was seriously confusing me was the combined wires the 2 greys an black that must be incorrect.
like each position from TB will only connect to a single position on the harness end correct.
additionaly for understanding the GM logic in wiring TB is also wired to the fuel injector like the TB is part of the fueling correct? not sure what low reference is maybe fuel injector thus throttle control.
side note me personably prefers older GMs w/ a throttle cable don't want these extra headaches.
thanks so much fastbrick for the schematics an advise. I wanta make sure this vehicle is wired correctly.
Originally Posted by RB04Av
D-GN = Dark Green
TN = Tan TN sounds like a telecom color code.
That's some of the NASTIEST home-brew wiring mess I've seen for awhile. I'm surprised any of it EVER worked, if it ever did.
yeah I recieved the H2 like this ducktaped wiring. I've been tidieing her up w/ good 3m electrical tape then cover w/ some corrugated tube .
and your correct this throttle body has been a intermitant problem one of the main reasons I haven't registered the H2 an start driving her BC I can't trust her.
thanks RB04Av
Last edited by thebrain; Jun 18, 2025 at 08:53 AM.
When I was an engineer at a telecom eqpt mfr, the color codes were:
L Blue
O Orange
G Green
N Brown
S Slate (grey)
W White
R Red
K Black
Y Yellow
V Violet (purple)
Definitely industry-specific. No one had ever even heard of the resistor color code; you know, the old "bad beer rots our young guts but vodka goes well get some now" system, except the mnemonic was less ... politically correct ... back in the day. GM used to use mostly 3-letter codes like blk, grn, ppl, etc. butt evidently wanted to save money on ink or something.
update on throttle control:
07 Hummer H2 am I unlearning the throttle body by removing battery prior to winter?
Just before winter I messed around w/ the throttle body wiring an have the wires sorted out properly an restored lost throttle control.
same as when I purchased the H2 couple years ago.not exactly sure what I did it may have been a series of starting her then turning her off which I'm starting to think could have forced a relearn of throttle body an the other related parts pac/pedal/emm an basicely restore throttle control , like all she'll do is idel, prior to whatever I accidentally did to restore throttle control.
I remove the battery an place on a solar trickle charger over the winter bc it's not driven.
today I started the H2 wanted to move it around the backyard an no throttle control again dam.do these throttle bodys fail intermittently or is this an unlearn process when battery is removed?
after I started the H2 let her idel for 5 minutes then I turned her off then again dissconnected the battery bc I'm not sure if there's a drain on battery, (I will eventually test for a drain when I start driving her).
so I came back a few hours later reconnect battery an connect my replacement inexpensive scanner (from post#6) up still no codes but merrackulessly I have throttle control.
what is happening? should I remove throttle body an spray some throttle body cleaner inside?like this
these tips I read from rockauto indicate something other than throttle body failing.this H2 has none of these simptums only idels an no throttle control control image
when I reconnect battery maybe I should be doing this relearn?
Loss of throttle control has nothing to do with the MAF.
Either you still have a wiring issue, The electronic portion of Throttle body could be faulty, or you have an issue with the sensor at the Pedal.
In order to Diagnose it and fix it properly you need a scan tool that is capable of showing Live data so you can see what is happening when you command it to open.
I was checking codes on my express 3500 the other day forget how I clicked to live data but this mickey mouse scanned doe's have live data.I assume the engine hase to be running to scan for live data? will check again thanks fast brick
I'll select this section for live data.
the objective to purchasing this scanner was to diagnosis the H2 no throttler. however my vehicals have a bad habit of making me look like an ******* like when diagnsising they act like nothings wronge dam.
Yeah you will need a bidirectional scanner. I suggest something from Autel's lineup as I have one of their scanners currently and don't really have anything bad to say about it.
Yeah you will need a bidirectional scanner. I suggest something from Aurel's lineup as I have one of their scanners currently and don't really have anything bad to say about it.
I searched w/ joogle an it came up as tv an appliances please post link for the decent bidirectional scanner.
I attempted to do a live scan data stream.
I did some scanning no codes an I had the engine running scanned about 7 minutes.the clicking you hear is two exhaust manifold bolts on driver rear cylinder I have the clamps just haven't figured out a easy way to install maybe though the wheel well.
update on the H2 progress:
I cranked her up a couple days ago same old chit differnt day no throttle control. so I clear the code w/ my el cheapo scanner an this restores throttle control. I've acutely done this a few times on differnt dates.
being able to restore throttle control though software would that indicate that the hardware wiring is correct? an this reoccurring no throttle issue is inside the throttle bodies sensor or maybe the throttle pedal?
I wrote down the codes. there where actuely 3 all related to throttle but missplaced the paper next time I report back I'll provide all 3 codes. thanks
update on the H2 progress:
I cranked her up a couple days ago same old chit differnt day no throttle control. so I clear the code w/ my el cheapo scanner an this restores throttle control. I've acutely done this a few times on differnt dates. being able to restore throttle control though software would that indicate that the hardware wiring is correct? an this reoccurring no throttle issue is inside the throttle bodies sensor or maybe the throttle pedal?
I wrote down the codes. there where actuely 3 all related to throttle but missplaced the paper next time I report back I'll provide all 3 codes. thanks
No all you are doing is clearing the code so it will function. The codes will tell you what's wrong and where to look.