NewbieWar

okay,
first I unplugged the TPS
put the key in, turned it to the ON position, did not turn it on.
adjusted my voltmeter to the 20v setting, (had many to choose from 200v, 20v, 200mv and 2000 mv)

at first I had it set at 2000mv incorrectly, but after I used the AA i realized the proper setting was 20v.

used the black prod, to touch the black wire's connection
used the red prod, to touch the grey wire's connection

even on the smallest 2000mv I got 0v (sometimes the (-) would show, but always 0) Tried multiple times, to make sure it wasnt fluke... doubted myself many times.

then checked the black prod against the blue wire's connection, 200 mv and i got about 28.0-30.0 but of course the decimal should be adjusted i think 3 places, maybe only 2...

I also checked at the 2000mv between the alternator bracket and the black wire connector, got a low reading, checked the grey wire and the alternator bracket, got 0. Not sure if the alternator bracket is supposed to be grounded or charged, right now, i can see how it could be either, being an alternator, and its connected to the battery, but also, the frame and engine mounts should be grounds.
Not certain if this is useful information, but to me it was more out of curiosity.

Guest47904

Set your meter to 20V scale. Turn key on engine off. Probe from gray to black wire of the MAP sensor with the connector unplugged. MAP sensor view.

This will tell you about your source. If not there we go to the PCM. If it is there, look at the wires going to the TPS

Let us know what you get.

NewbieWar

Hate to be picky, but that is a confusing sentence...

I'm assuming, you mean turn the key to the on position, but the engine is off.

but it could mean, the key is turned to the off position.

Dave1980

any turn of the key would be in some kind of on position. He certainly means no start.

NewbieWar

okay, just wanted to get conformation.

i'll go check it in soon

NewbieWar

black and grey wire on MAP is 4.99v

Guest47904

Ok so now we need to see if the 5volt wire is the problem to the tps or if it's the ground reference. So using the MAP plug and the TPS plug do the following.

Measure from the gray wire of the MAP to the black wire of the TPS. Same conditions as before. If it reads 0, the black wire is the problem going to the TPS. If it reads 5 volts then do the following.
Read from the Black wire of the MAP to the gray wire of the TPS. If it now reads 0 volts, the problem is the gray wire going to the TPS.

Note, if both tests passed. Then you have to attach the probes to the wires so you can free your hands to wiggle the wires while observing the meter.

Let us know.

NewbieWar

Awww, Injuneer pulled his comment, thanks for telling me about the phrase: Key On Engine Off. I realize my statement was truly more confusing than the one I was complaining about.

Black MAP Grey TPS 0v
Grey MAP Black TPS 4.99v

Guest47904

So it's obvious the gray 5volt reference wire going to the TPS is the problem. So here is the easiest way to find the problem.

Be sure the black meter probe is connected to the black TPS wire. Now pierce the gray wire about a foot from the TPS with KOEO and see if you have 5 volts.

Be careful here for 2 reasons. First, if you don't get all the way through the insulation, you will not get a reading and could mistake that for not having voltage there.

The other reason is if you're not careful the probe will slip off the wire and jab your hand/finger so do something to prevent it.

If 5 volts is not there, find the break on the wire between that point and the PCM. If 5 volts is there, find the break between that point and the TPS connector.

Guest47904

Hello, just wondering if you were going to update us.

NewbieWar

well, i havent got much chance to work on it... keep in mind its about -10* here in germany right now... and there is snow everywhere, a bit cold for my fingers to be touching metal...

however, i did check about 3 inches away from the plug, and at first i thought i was getting a small(.3 volts) reading, but realized it was because i was touching my finger and the cable at the same time...

I will have to try to pull the wire out of the plastic shrouding, to check further way. Sorry, i'll go check right now, engine should be warm

NewbieWar

okay, well now i'm throughly frozen... however, i checked it right after the MAP disembarks from the harness, and still got 0v

I realize now, my original complaint that it had electrical tape is all from factory, comparing it with shoebox harness pictures.

Where else should i check since the wire appears to be dead, and its not a problem at this end? all of the wires are still in the original bundles, so why should I assume it was broken half way between... is there a way i can check near the PCM?

(i've never removed the PCM, while I know where it is)

Injuneer

Did the wiring in 94 differ from 95? Shoebox's 95 diagrams show the +5V for the TPS comes directly from pin B28, with nothing else on the circuit. +5V for the MAP comes from pin B29, and that pin also serves the AC temp sensor and pressure sensor, and the IAT sensor.

I don't have the 94 diagrams, so I can't check.

Actually, from the signature, its hard to tell whether we are taling about the 94 or the 95?????

Guest47904

Interesting point about the 94 and 95. I did not know they were different. I was using the 94 shop manual I have. So now you know how 94's are wired. Another interesting point. We don't know which one he's talking about. Oh well.

Since you said the 95 has a difference, I've looked everywhere on shoes page and can't find it. Where can I find it?

Injuneer

Look at the PCM wiring diagrams. Its on sheet 1.

http://shbox.com/1/1995_pcm1.jpg