1989 PCM pin out ?

[Shoman594]

Hey Guys,

Does any one have a pin out picture for the PCM for an 89?
I have both 89 shop manuals and can't find it, maybe its in the mitchell manual?

I have to track down a short in the TPS sensor circuit

 

[Banshee]

I don't know how to post it here from my tablet but I believe there is a a printout if you scroll down under forum .how to guide .installing sho motor in something else.

 

[sperold]

Go on E-bay and find a Ford Electrical and Vacuum Troubleshooting Manual (EVTM) for the 89. They are usually available, and the ones in less than perfect condition are a good value. There are specialty companies that gather this old material and re-sell.
It will have all your information.
The regular Maintenance and Repair Manuals do not cover this topic.

 

[Off Road SHO]

I've lost my 91 EVTM otherwise I would be able to help you more. There is one on Ebay now for 12.00 with shipping. What are the symtoms and where did you test for the short?

Tom

 

[One_Shot]

The TPS is on pin 48 at the ECM connector and is a dark green/light green wire. I don't have a picture of the actual pin location in the connector but I hope that helps you out.

 

[Shoman594]

Thanks One_Shot.

If any one still has a print out please let me know I even have the EVTM manual and can't find it

I am looking for something like this

http://ww2.justanswer.com/uploads/tracker40/2011-06-25_103624_1.gif

 

[Shoman594]

Also on the short Tom, I mean i think its a short.

For example when I grab the wire loom from the TPS area i can make the car act up and move up and down RPM.

I have to think that i have a bad connection in there somewhere. Not sure the best way to tackle this.

 

[Shoman594]

still need some help with this hoping to dig into it this weekend. :/

 

[Off Road SHO]

My last reply didn't show up for some reason. Did you get it figured out?

Tom

 

[Shoman594]

Hey Tom, no not yet.

Basically what happens is when you take it out when its cold intermittently when you press on the petal you get nothing like a dead petal.

It used to have a up and down low idle for a while warming up until I was moving some of the wires under the throttle body and all of a sudden the idle smoothed out.

I checked the TPS with a volt meter and it counts up properly when i open the throttle with out any cutouts. Thats why i was thinking it was something in that wire loom.

 

[Shoman594]

Help

 

[kevinspann]

Wouldn't a pin-out for an X2J work, since the PCMs are swappable between MTX cars?

 

[Shoman594]

Wouldn't a pin-out for an X2J work, since the PCMs are swappable between MTX cars?

Sure. Does anyone have a pin out of a x2j?

 

[kevinspann]

Attached, sourced from Paul Nimz' supermotors account

 

[AREA 91]

Check the wires to the Idle Air Bypass valve.

 

[pjtoledo]

I would be concerned about the power to the TPS. the same 5 volts powers most of the sensors, some of the splices may be corroded. its circuit 351, brown with white. the return for the sensors is circuit is 359, gray with red. the signal for the TPS (throttle angle) is 355, gray with white.
at the pcm pin 26 is cir 351 power to sensors' it is an output from the pcm to all sensors.
pin 46 is cir 359, sensor return.
pin 47 is cir 355, throttle angle sensor/tps


this is from a 91 book, should be the same for an 89.

Bizzy could tell you what happens when that 5 volt sensor power circuit is compromised.

AH crap, just noticed this is for a 3.8 engine,,, let me do some more reading.

good news , the pin outs are the same for those circuits.

Perry THE RANGER GUY!!!!!

 

[Shoman594]

Ok great this is something to go on!

Brian when you say check the iab valve wiring I'd this the same as perry is talking about how the circuit is shared ? And any drop in that 5v circut could cause the issue? Still trying to also figure out why it only happenes while cold or on warm up

 

[Shoman594]

Ok went into it a litte lore when I move the grey plug in the pic I attached the check engine light goes on and the idle drops where it almost dies. Should I start to open that part of the harness ? Ideas?

 

[pjtoledo]

this is from a 91 EVTM
the idle air control & idle speed control solenoid both get power from the ICM on the same circuit as the injectors. should be 12 v
then they each go directly to the EEC. they do not interact with the 5v sensor power circuit.
both power and ground from the TPS go thru connector C133, and at least 2 multi-lead splices.
one is before the connector, the other is after the connector.

 

[pjtoledo]

in the 91 EVTM the pin-outs are in section 150,, connector faces/pinout charts
same as is posted above.