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Pink is swicthed 12V. It gets juice from the ETC/ECM fuse. The schematic I have is different than the one provided above but may have the same pinouts, haven't had time to compare them side by side.
Here's BOTH of the GM schematics I have for a 2003.
http://img147.imageshack.us/img147/5103/834728ah0.png
http://img241.imageshack.us/img241/3395/56978265vx8.png
thanks gassguzzler.
img 241 matched well. it had a ground (15) that wasnt listed in the other one.
This is what I know, ya'll tell me what to think...cause Im thinking bad TACM.
This is in reference to IMG 24 in gassguzzlers post.
All tests done with key on and a test light. Test light was grounded for power tests and hot for ground tests.
7 pink 12v switched. YES works fine.
15 ground. YES works fine.
3, 10 low reference. NO, did not show to be a ground.
2, 9 5V reference. NO, no voltage present
1, 8, 11, 16 werent sure what to test for, so we left these alone.
Correct me if Im wrong but the 5v reference should be hot key on and the low reference should be ground, usually the case but is there something special about this one?
Bad TACM? Hes gonna get a new one if we determine it faulty, this little bastard of a gem is $150, would be money well spent if its the problem but a fair hit if its not.
Let me know what you think.
3 and 10 should show ground when testing AT THE THROTTLE BODY CONNECTOR terminals D and B.
Same for 2 and 9. They should show 5V at the T/B terminals H and E. Use a meter, obviously 5V won't light most test lamps.
1 and 11 could be tested using a jumper and a scanner. If you unplug the T/B and jump G to H you should see 5V on the scanner for TP1 (provided the 5V tested good earlier). Same for E and F for TP2.
All tests above should be done with the TACM plugged in and key on.
8 and 16 sould only be tested for continuity end to end (16 to A and 8 to C) with both the TACM and TB unplugged.
test light had been lighting on 5v up to this point but well try the meter, see if there is anything at all.
thanks
here is what I have.
harness at throttle body. key on
3 and 10 are solid grounds.
2 and 9 both shown 4.97v
8 and 16 shown minimal resistance, so they are ok continuity wise.
harness at TACM to APP
5v reference wires.
D - tan - 0v
E - yellow/black - 0v
G - white/black - 4.95v
low reference wires
A - gray - 5v
B - purple - 4.95v
J - brown - 0
sensor signal wire
K - dark green - 5v
The low reference and sensor signal wires shouldnt be showing anything. The TB wiring was fine I guess, we dont have a scanner to jump 1 and 11 but I doubt that would explain the screwy readings at the TACM.
What do you all think? I was thinking bad TACM but he tried two and both shown the same exact thing. So now Im not so sure.
There are two connectors on the TACM, correct? There may be the same color wire in each connector. Still haven't looked closely again myself.
yeah.
ok, maybe I was a little tired when I wrote this info down. :D
update
TB side seems fine, although without a scanner, we didnt jump 1 and 11, which could very well be the source of the problem, I dunno. is there a way to test these with just a meter?
found 5v at the APPS connectors that are 5v reference. also found 5v at the green wire (k), which is interesting, as nitrous schematic lists this as a signal wire, where yours list this as NOT USED. Now if it was a signal wire, I dont think it should show 5v and couldnt this translate to the pcm thinking the throttle blade is open all the way and explain the high idle and no pedal function? Im grasping for straws here, as in reality, I have no idea what this signal wire does.
any thoughts
This is getting old....
If someone has a last minute suggestion, feel free to throw it out here, as the trucks getting towed to a shop tomorrow, gonna put a scanner to it....
Get an 02 and earlier DBC setup, pcm and wiring harness and throw that electronic crap in the garbage. :laugh:
believe me as soon as I dig myself out of the hole a bit that is going to be dealt with. I have a feeling this is going to be a issue (DBW).