what wires for v6-v8 tach (98 sport)

[vroomzoomboom]

this is staring to drive me nuts. just did my 8v swap in my sport. according to this thread (around the 10th post)

http://www.explorerforum.com/forums/showthread.php?t=209963

I can save you some research.

On the back of the cluster are 3 connectors, 10-, 12- and 16-pin. Look at the short 10-pin and you will see a black/yellow ground wire in pin position #8. Now look at the 16-pin and you will see an empty slot in position #16. Release the black/yellow ground wire from the 10-pin and move it to the #16 slot of the 16-pin. That's all it takes to convert your V6 truck to read V8 RPM.

so i pulled that wire out of the connector

but when i went to put it into the 16 pin connector it was like this

going from a thread that corkey found for me from TRS, it should look like this

im a tad stumped here. can anyone help? i DO NOT want to either put that wire in the wrong spot, or ground it incorrectly in fear of blowing something that i will need. the truck is a 98 sport that had a SOHC in it, and the motor is also from a 98. i tried changing the circuit boards on the back of the cluster, and that didn't work. i also tried the cluster from the v8 truck, and that also didn't work. the tach reads way to fast, and want it to read correctly.

 

[2000StreetRod]

message center?

I don't have a 1998 wiring diagram but according to my 2000 wiring diagram the tachometer signal is generated by the PCM and exits via Pin 48 (tan/yellow wire). It goes to the instrument cluster (Pin 15) and the message center (Pin 34). I suspect it is just an analog signal with the voltage varying according to the engine speed. If your tachometer reads high but varies with engine speed then the output voltage scale is incorrect. The message center has an "engine select" input. It is Pin 32 on my model but may be different on yours. However, the wire color (black/white) may be the same. If the input is open (no connection) V6 is selected and if the input is grounded V8 is selected. The pins and wire colors look the same for 1996. My Sport does not have a message center. Maybe all of the V8 models had one.

 

[vroomzoomboom]

Well I wired my m/c in. It never had one from factory. Same with the donor truck, it didn't have one either (it was a xlt). What I don't understand is why I would have a wire in pin 16 one the 16 pin connector. I would have to think my 98 is wired the same as your 00.

 

[2000StreetRod]

V8 pcm?

After further consideration it seems unreasonable to me that Ford would rely on a message center in order to display correct tachometer readings. The V6/V8 select (pin 32) probably allows the use of a common message center.

The instrument cluster connectors and pinouts shown on my 2000 wiring diagrams are significantly different from the ones you have posted. However, many of the signals have the same circuit numbers and wire colors. I did not notice any V6/V8 select signals on the instrument cluster connections. The tachometer appears to be a simple voltage or current reading analog device.

Are you using the V8 PCM?

I just noticed on the C216 pinout you posted that there is a 3.0L, 4.0L GND pin. I suspect it is for a Ranger instead of an Explorer.

 

[vroomzoomboom]

yes, i am using the v8 pcm (didnt know it would run if it was the v6 one)

yes, that is a ranger one. i should have said that. whoops! however, i was looking at the printout my buddy did for me on a 98. for a SOHC, pin #8 on the connector with the ten pins as ground (black/yellow) and pin 16 on the 16 pin connector as ground as well (black/white). then in the same diagram, it shows for a 4L ohv, and the 5L #8 on the 10 pin as ground (black/yellow) and pin 16 on the 16 pin connector as open. now if both of these are ground, i am wondering if i leave the black/yellow wire unhooked if this will work. i am gong to try it tomorrow. if that does not work, i will try the black/yellow in pin 16 and the black/white open. hope it works, because i hate dead, and or gauges that dont done work correctly.

 

[2000StreetRod]

ground pin 16

I would be very surprised if a V8 would run with a V6 PCM but I thought I should ask. The ignition and fuel injection timing would be way off and only 6 of the 8 cylinders would have spark and fuel.

I found a note for my 16 pin connector which is C286 on my 2000. It says pin 16 (BK/WH) should be ground for 5.0L. I also found a note for the 10 pin connector which is C288. It says pin 8 (BK/YE) should be ground for the 4.0L.

The note on the wiring diagram page says C286 pin 16 is grounded if the message center is present. The inconsistency is rather confusing.

The instructions in the post by rwenzing are correct: http://www.explorerforum.com/forums/showpost.php?p=1884375&postcount=10

 

[vroomzoomboom]

so i figured it out, and a little embarrassed by it to. all you have to do is take the black/yellow wire from pin 8 out of the 10 pin connector, pull the black/white wire from pin 16 in the 16 pin connector, and replace it with the black and yellow wire. i just put some tape around the black/white wire in case it did for what ever reason hit something that was live. and thats all.

 

[crazyflights]

Hmm, my engine is from 98 and my body is 97, My tach reads way to fast. Wonder if this will be same for me, haven't had time yet to trace down all my little wiring issues. I bet this is the same.
I will give this a try this weekend.

 

[vroomzoomboom]

try it out, and let me know. at idle it was reading 1100-1200 rpms, and when standing on it, it would red line well beyond 6000 rpm going off the tack.

 

[ahodges]

I had the same senario as you vroom. I have a couple more complications though. When I did that, I lost the O/D off indicator light.

Other problems I have though is i can't get the speedometer to work and the fuel gauge is pegged on full. I think the fuel gauge might be the new sending unit I put in (Spectre i think). I'm more concerned about the O/D light and the speedometer. Thoughts??

 

[vroomzoomboom]

do you still have the other truck you took the motor from? maybe try those gauges in it. if i am not wrong, 95 96 gauges have some kind of resister that screws with everything, an makes life miserable for the owner.

 

[ahodges]

hmm. well I made a hybrid gauge cluster between the 2 trucks. I basically swapped the entire gauge clusters minus the pod with the tach and odometer. I kept the original odometer with the right vehicle. The 96 cluster works in the 97 mountaineer with the V6 installed.

I haven't confermed this yet but I think that the lack of O/D off indicator might be because I didn't plug the dimmer and head light switch back in yet, I noticed that the 4X4 lights stopped working as well.

I'm still stumped by the speedometer though It seems like the sensor is working because when I connect my laptop to it through livewire I can get a speed reading. :scratch:

 

[ahodges]

Speedometer problem is a lack of the worm gear on the tail shaft to drive the speed sensor....

 

[vroomzoomboom]

glad you solved one problem. any luck with the others?

 

[ahodges]

Yeah, the O/D indicator light and 4X4 lights were because I didn't have the dimmer switch pluged in when I was testing it. I think that about solves all my electrical issues except for still needing to install another fuel gauge sending unit in the gas tank. I haven't had much luck with aftermarket stock parts on this build, nor with any others; You would think I would learn!

 

[Explodedford]

Do you guys think I can do this in my 96 that I just swapped a 5.0 in ? I have the stock v6 96 gauges

 

[ahodges]

Yes. It will work without a problem. Read through this thread where I start talking about swapping from a 97 mountaineer into my 96 explorer. If you have further questions don't hesitate to ask.

 

[Explodedford]

Thanks man I'll let you guys know how it turns out