89whitetoyota

Ok, so it seems like I have a code 22 (engine coolant temp sensor) and a code 41 (TPS circuit fault)

I did the terminal jump and I got this (I will do it somewhat of Morse Code) –
_ _ (2 sec pause) _ _ (5 sec pause) _ _ _ _ (2 sec pause) _ (long pause) then it would repeat the former.

I assume this is –

(2) (2 sec pause) (2) (5 sec pause) (4) (2 sec pause) (1)

So when I replaced the IACV on the throttle body I replaced the engine temp sensor also (next to the cold start switch under the throttle body). It has the green connector and is brand new, not sure why that would throw a code.

Then the code 41 is a TPS circuit fault – does this just mean the sensor is messed up or the whole loop is messed up? The TPS checked out when Ohming it.

thook

What you should do is unplug the connector at the ECU and run the same resistance tests. Not on the ECU itself, but the corresponding connector terminals.

http://personal.utulsa.edu/~nathan-b...ne/44engin.pdf

Possibly you have a bad connector at the components or bad wiring.

89whitetoyota

Ok which ports on the connector should I check? I cant tell which ones go to the TPS, or at least it doesnt seem blatantly obvious.

I have never checked wiring from connector to connector so if you could gimme some basic electric advice that would be much appreciated.

thook

Looking at the diagrams on the link, the diagram that applies will be labeled 4wd m/t.

For the coolant sensor, look for THW (means thermal water) and E2 (which is ground or earth). Following the same instructions you ran for the component itself, run the test at the those terminals.

For the TPS, you will have VTA (throttle angle), IDL (idle contact), Vcc (voltage supply), and E2. Those are also evident at a diagram for the TPS itself. Again, run the same test following the same instructions you did at the TPS.

However, considering the nature of bad wiring or a connector, you may not need to follow through with the entire procedure. You may find that you won't get a meter reading from the start. That'll reflect as an open circuit, or "0", on your meter. This would mean either the terminal in the connector has backed out or broken or the wiring is broken somewhere. If you have a short in the circuit, though, you get inaccurate readings. This would mean you probably have an exposed or partially broken wire somewhere making contact with something it shouldn't be......like another bare wire or the engine.

If all these pass, though, you'll need to test the ECU itself.

thook

BTW, the terminals on the connector are not labeled. You'll need to go by the ECU pins and mark the corresponding connector terminals so you are certain you're at the correct ones and not testing some other circuit. Use a marker or something that can be cleaned off.

89whitetoyota

Thanks for the very understandable instructions. I see what to do now. Thank you.

thook

Yah mon....