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OBD II Wiring Diagram


muwaha

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Hey All,

I finally got my 2000 Ranger 4.0 OHV fixed.
I broke down and took it to the shop.. Turned out to be a clogged catalytic converter.
The Mechanic tried his scanner (on top of my Launch, Innova, and Actron) but couldn't get communication from the ECU (is what the scanner says).
It won't read anything from the ECU, PCM, or DATs (If I recall that is the correct term).

So I replaced the PCM Relay, #17 Fuse, but still no communication.
I think I got a broke wire/pin.

What I am hoping to get out of this forum is someone that has the wiring diagram of the OBD II port, so I can start tracing wires.
(Yes, the truck does run now, the mechanic straight pipe, so the CEL is on as a result of the rear 02 Sensor so the PCM seems to be doing it's job except for sending the data to the OBD II)
 


franklin2

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Hopefully this is all of it, but I am not sure. It shows 7 wires. Count how many wires you have to your connector.
 

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RonD

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This one may be easier to read

1995 thru 2011 Rangers use the same OBD2 connector and wiring, same even now as far as the OBD2 plug in, or the readers wouldn't work

The PCM pins changed in 2007 when PCM went from 1 connector to 3 connectors
 

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muwaha

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Thank you both @RonD and @franklin2.
I wiggled the wires right behind the OBD II port and got my 25 year old Actron CP9410 scanner to work, but my Innova 5410 and Launch CR123 refuses to scan for some reason.
I already sent a support case to the manufacturers asking why do they not work.

My Actron detected an issue with the Rear 02 (from where the mechanic straight piped), and a misfire on Cylinder 4.. Now I just got to figure out which one is Cylinder 4 on the block haha.. I've seen multiple sources showing contradicting information.
 

RonD

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Ford numbers cylinders front to back starting on the right(passenger side)
GM(Chevy) uses ODD and EVEN starting at front left and chris cross

Ford V6
3 6
2 5
1 4
Front

GM V6
6 5
4 3
2 1
Front

Ford V8
4 8
3 7
2 6
1 5
Front

GM V8
8 7
6 5
4 3
2 1
Front

Inline are the same for both, 1 2 3 4, or 1 2 3 4 5 6
 

muwaha

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@RonD Thank you for that information. I thought that was the case but the Coil Pack screenshots that showed which coil went to which spark plug was what was confusing me.
Below is what the difference in the coil packs were, I kept thinking to myself this might be the difference between the OHV (which is what I have) and the SOHC.

This is what kept throwing me off lol.. I kept trying to go by the coil pack positions and google was confusing me.

Example 1:
3 4
2 6
1 5
Coil Pack side facing you
Front of Engine


Example 2:
3 5
2 6
1 4
Coil Pack side facing you
Front of Engine
 

RonD

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The coil pack wiring reflects firing order(cam/valves) and the Matched Pairs of pistons in an engine

To balance a multi-cylinder engine the pistons are set up in Matched Pairs, two pistons will be at TDC at the same time
In the case of a V6 that would be every 120deg of crank rotation, V8 every 90deg, 4cyl every 180deg

3.0l or 4.0l Ford V6 uses this firing order 1-4-2-5-3-6
To find the "Matched Pairs" on any engine just spit firing order in half and put 1 half above the other
1-4-2-
5-3-6

So the Matched Pairs are 1/5, 4/3, 2/6
The coil pack reflects these Matched Pairs
[3 4]
[2 6]
[1 5]

Ford uses Waste Spark, so there are only 3 coils in this coil pack
Spark plugs 1 and 5 spark at the same time, one will be on compression stroke, the other on exhaust stroke, so the exhaust stroke cylinder's spark is "wasted", hence the name "waste spark"
Waste spark is the very first spark system ever used, uses the crank shaft to time spark instead of the Cam shaft, single cylinders still use it, and Ford and other car makers as well

Not sure where this one would come from?
3 5
2 6
1 4

I would guess a misprint or for a non-Ford V6
Its firing order would need to be 1-5-2-4-3-6
1-5-2-
4-3-6

GM(chevy) maybe, they number cylinders differently as said earlier
 
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