Need PATS help on 93 ranger swap

[farmhanddunc]

You are using the 104 wire PCM(computer) right, have to ask

And the instrument cluster for that PCM?

Yes 104 wire pcm. Using the stock 93 ranger cluster at the moment. The wire from the cluster that controls the CEL lights up when I jump 12V to it if I remember correctly


Sent from my iPhone using Tapatalk

 

[RonD]

1994 cluster wiring here, it will be the same as '93: http://www.therangerstation.com/forums/showthread.php?t=170249

The CEL(MIL) gets 12volts when key is ON from fuse in cab fuse box
In the pre-'95 it was ground by pin 17 on PCM, with 104 wire PCM it pin 2 that is the Ground for the CEL to light it up

 

[farmhanddunc]

1994 cluster wiring here, it will be the same as '93: http://www.therangerstation.com/forums/showthread.php?t=170249

The CEL(MIL) gets 12volts when key is ON from fuse in cab fuse box
In the pre-'95 it was ground by pin 17 on PCM, with 104 wire PCM it pin 2 that is the Ground for the CEL to light it up

Pin two is connected to pin 17.

 

[RonD]

PCM Pin 2 is connected to Previous pin17 wire(pink/green stripe)

Then CEL should work normally, glowing would mean problem in instrument cluster or cab fuse box wiring

Fuse 7 15amp in '94 powers all the gauges and warning lights.
Do all the other lights come on and then go off when key is turned on, i.e. a bulb test

 

[farmhanddunc]

PCM Pin 2 is connected to Previous pin17 wire(pink/green stripe)

Then CEL should work normally, glowing would mean problem in instrument cluster or cab fuse box wiring

Fuse 7 15amp in '94 powers all the gauges and warning lights.
Do all the other lights come on and then go off when key is turned on, i.e. a bulb test

Yes. Fuel gauge moves and so does voltmeter. However when I tried putting 12v to the 93 wire that is supposed to be for engine temp I got nothing.


Sent from my iPhone using Tapatalk

 

[farmhanddunc]

okay so been prodding with a test light.

on the fuel pump relay (using the 93s) the red wire is always hot even with key off. and the LB/O wire has enough juice to make the test light glow a little. It is tied into the DATA LINK wires as well if i recall like the CEL light. maybe a short or something causing backfeed here could be the source of all of my problems?

 

[RonD]

Red wire at FP Relay should only have 12volt with key on, it comes from PCM Relay closing, thats for the FP relay's Coil
The Light Blue/orange wire is the Ground for the coil, it was connected to pin 22 on old PCM and did also connect to the old Data link ODB1 connector in the engine bay
This wire should not be connected to OBD2 data link wires, it should go directly to Pin 80 on the new PCM, FP Control

The 1998 Explorer fuse box is wired differently, so I assume you are using the 1993 engine fuse box?

 

[farmhanddunc]

Red wire at FP Relay should only have 12volt with key on, it comes from PCM Relay closing, thats for the FP relay's Coil
The Light Blue/orange wire is the Ground for the coil, it was connected to pin 22 on old PCM and did also connect to the old Data link ODB1 connector in the engine bay
This wire should not be connected to OBD2 data link wires, it should go directly to Pin 80 on the new PCM, FP Control

The 1998 Explorer fuse box is wired differently, so I assume you are using the 1993 engine fuse box?

Yes i am

 

[farmhanddunc]

Alright i feel ive made progress but still no start.

I removed the old OBD port and installed the OBD II port from the explorer. this took care of my CEL light problems.

I still have no light pulses when i stick the test light on the wire for the PATS indicator.

i still can not get the fuel pump to turn on.

NEW ISSUE: i discovered that the reason the red wire in the relay is always hot is because the power (VPWR) wire from the 5.0 is feeding them 24/7. it was also my understanding that this "receives start/run B+ from the BJB PCM Power Relay to provide voltage to operate Fuel Injectors, Idle Air Control (IAC) Valve and the Mass Air Flow Sensor (MAFS)". So this wire should not be hot and should be taking power from the EEC relay.


attached is the half ass spread sheet i made to cross reference things

 

[farmhanddunc]

Can anyone confirm this should be taking voltage not sending it?


Sent from my iPhone using Tapatalk

 

[farmhanddunc]

i had wired the LB/O wire that was only hot from the power distribution box to hot at all times. this was back feeding the vpwr to hot. this is fixed now.

still no fuel pump

 

[RonD]

With fuel pump relay removed, Key OFF
You should have 1 slot in the relay's socket with 12volts, thats from a local fuse

Then key ON there should be another slot that now has 12volts, thats from the PCM Relay

Automotive relays are pretty standard, 4 pin layout here: http://www.12voltplanet.co.uk/user/Driving_light_relay_wiring_diagram.png

5 - pin just has another pin below 87, usually unused even if there
Pin 30 or 87 will have the Full time 12volts

85 and 86 are used to activate the relay, with key ON either 85 or 86 will have 12volt, 0volts key off
The OTHER one is the Ground, computer(PCM) controls this, so PATS controls this
When key is first turned on this slot should be a ground for 2 seconds
This wire is Light Blue/Orange stripe, and should have 12 volt with key on if FP Relay is in place, 12v from PCM Relay goes to FP relay's coil(Red wire) with key on, passes thru the coil and down the Light Blue/Orange stripe wire to pin 80 on PCM

 

[farmhanddunc]

With fuel pump relay removed, Key OFF
You should have 1 slot in the relay's socket with 12volts, thats from a local fuse

Then key ON there should be another slot that now has 12volts, thats from the PCM Relay

Automotive relays are pretty standard, 4 pin layout here: http://www.12voltplanet.co.uk/user/Driving_light_relay_wiring_diagram.png

5 - pin just has another pin below 87, usually unused even if there
Pin 30 or 87 will have the Full time 12volts

85 and 86 are used to activate the relay, with key ON either 85 or 86 will have 12volt, 0volts key off
The OTHER one is the Ground, computer(PCM) controls this, so PATS controls this
When key is first turned on this slot should be a ground for 2 seconds
This wire is Light Blue/Orange stripe, and should have 12 volt with key on if FP Relay is in place, 12v from PCM Relay goes to FP relay's coil(Red wire) with key on, passes thru the coil and down the Light Blue/Orange stripe wire to pin 80 on PCM

the LB/O wire doesnt appear to be getting grounded for the first 2 seconds. when i touch a test light i get a 12v light for the red and black/yellow wires (when the key is on and relay in place) but nothing for the green/yellow wire. when i touch to the LB/O i hear the relay engage and hear the fuel pump. the test light also glows dimly. this all stops when i remove the test light.

so the ECM isnt grounding the LB/O thus not giving any 12v power to the pump or back to the ECM via the pair of DG/Y wires

 

[farmhanddunc]

While going back over some of the swap links in the tech articles I came back across one article that says to swap PATS onto a non-PATS vehicle I must have the steering column from the explorer. It doesn't touch on this anymore. I don't see anything missing from my wiring diagrams. Is there something inside the column that could be fouling up the PATS system?

Also could the lack of a RAP module cause the system not to function?

Sent from my iPhone using Tapatalk

 

[farmhanddunc]

update:

aslo noticed that when i turn the key to on only the seatbelt light on the dash comes on. when key is turned now