Quad cab swap done but have a few issues need advice before I pull my hair out

S

Slowrockr

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I'll start with what I have/did. 96 12v manual truck put complete 00 v10 quad cab on it, dash and all. Using 98 pcm and engine harness hooked to the v10 fuse box and wiring. Swapped sensors to 98 12v so it all plugs in correctly. Obviously the v10 had no pin to power up the fuel solenoid relay so tapped that in. My first issue is it will hold the solenoid open with key on but won't pull it open when cranked. Even when I open the fuel shut off and start the engine I get no tach and no charging. Yes I searched and read several engine swap threads and seems like most using the 98 pcm and harness it's plug and play but most all were 24v to 12v. I can communicate with the pcm, abs, body module etc but show no crank rpm or running rpm on the scanner.

Second issue is my gauges and for all I know is part of the same problem or the problem. They seem to work minus the tach and speedo (pegged at 120, haven't worried about that yet) but dash does say no bus. I'm gathering I need to ditch the v10 cluster for the diesel cluster but looking to confirm this. If so do I need 98 only to match the pcm or any 98-02 work? Seen people say the gas tach will work in a diesel so I thought I may be in luck but starting to think not.
 
I've put a gas tach (whole gauge cluster)out of a dakota, IIRC (might have been a ram), in my buddys 98.5 24V and it works fine. speedo and everything worked. the only thin was the wait to start light is now something else like 4X4 low or something.
 
does it still have a crank sensor on the balancer? if so did you check the gap, if its too big you wouldn't have a tach or charging. Oh and i just remembered, when we first put that cluster in my buddys truck the tach and speedo were both pegged, he revved it and the tach started to read fine, then he drove it and the speedo started to work fine, its like they had to get a baseline reading or something....
 
Yea still has the crank/engine speed sensor on the balancer. The 98 engine harness has a 3 flat plug and my 96 had 3 pin round. I searched and found few posts saying same sensor just different plug. The V10 crank sensor had the correct plug so I used diagrams to match up wires and swapped the plug. It worked in the 96 dash and I didn't unbolt it to solder the new plug on so never checked gap on the old sensor. Thought maybe I screwed up and didn't pin it right so I got a new sensor for a 98 and still no dice.I'm gonna take a step back and ohm out from the sensor plug to the pcm plug. Just want to make sure the V10 fuse box wiring isn't moving the signal wire to the wrong pin on the engine harness. I'm getting a good ground and 5volts at the sensor plug and the pcm communicates with the scanner fine so I doubt it but just wanna know for sure.

I've been searching like crazy and am pretty convinced I need a different cluster to fix my no bus problem. Just not totally sure if the problem is a year incompatibility or if it's because this was a gas cluster. And still not sure if maybe the no bus communication cluster crap is causing the whole problem, confusing the whole system or something stupid.
 
Your problem is in tachho senor or bad ground.

I have also Gas truck gluster in my 98 12V.

Do you have automatic ecu and engine harness in manual truck?
 
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No manual pcm and harness, ground at sensor is good as is 5v signal. Aren't clusters different from some years to others? Meaning the bus signal stuff? It is an auto cluster could that make the difference?
 
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If the ECU/PCM do not see the tachho signal, it will not hold shut off solenoid and will not charge.


Currently I have no wiring schematic near me, but I think your problem is tachho signal related.

On tachho harness have 3 wires : 5v , ground , signal


edit: all 98 trucks with different engines (including 12V) have the same under dash harness , difference is only in power options

Even the under hood harness difference is minimal
 
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K, I have access to shopkey and have pulled diagram to trace it. Power (5v) and ground at sensor plug are correct, has to be in signal wire somewhere. I'm out of town til Monday but gonna check it Monday. Fingers crossed its broken wire and not a worse issue.
 
V10 fuse box wiring didn't have the starter signal wire to the fuel solenoid relay. Wired that in and it will pull solenoid open now but still no tach. Reset gap on ess to .050 still no tach. 5v is present at sensor as is good ground, signal wire is good from sensor to pcm. Pulled codes only code present is wait to start light which isn't there in the v10 cluster. Still showing no bus on dash, did cluster self check and all works just says no bus. Going to check bus wires and make sure they too aren't pinned wrong or missing in the v10 fuse box to engine harness plug. More searching has me leaning towards the auto v10 cluster not being correct for the 98 manual pcm but going to check basics first.
 
Bus wires are in correct pins and are good from one end to the other. No matter what I try I can't get any rpm signal on the dash or showing on the scanner, kinda wondering if this pcm may be faulty. Unless I had the bad luck of getting a faulty new ESS. If the year difference from cluster to pcm are no big deal that would lead me to think bad pcm which would be my luck. :doh: Any thoughts before I start hunting PCM's?
 
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Thanks for posting this. I'm fixing to do the same swap with my 94 c&c truck. To make it a quad cab short bed. I'm sure I will have my share of troubleshooting. Good luck with finding the problem I'm interested in what you find.
 
Yea revved it to prob 2k. Everything communicates and passes self tests but the cluster. Probably going to get the cluster out of the same truck the pcm came from. I'd rather have it look correct with the manual diesel cluster anyway and maybe it'll fix the no bus issue. Still not sure what's with no tach signal though. I love my 12v and it pulls the 40' race trailer like its nothing, I have no problem going thorough a few headaches to give it a face lift.
 
OK, that was my only suggestion.

Any time I have removed the dash cluster on my 12 valve, I had to rev the motor a little for the tach to work.
 
I'm not showing rpm on the scanner either, going to look at that issue a little more this evening. This cab was a work truck and somehow they made it 316100 miles with the v10, for all I know the cluster was already messed up. Got the cluster from the truck the pcm came from on the way, guess I'll find out in a couple days.
 
It's a 2000 v10 cab, I used the fuse box and under hood wiring from said truck and put a 98 12v pcm and engine harness on it. The pcm is only looking for the crank/ engine speed sensor signal for rpm. Until the cluster shows I'm gonna just double check the sensor wiring to pcm and tie up some other loose ends. I'm still unsure if the wrong cluster could be causing it since it's tied into the whole bus system. Not completely sure how they all talk to each other and if the cluster sends any kind of "hey I'm here tell me what you know" signals back to pcm or what. I would hate to waste a bunch of time trying to diagnose something the cluster may fix.
 
Part of me wonders if swapping the V10 PCM back in and plugging the diesel wiring harness into it would make it work?

Also, PM 17cumminsboy as he did a very similar swap and I'm pretty sure he had a no bus on his gauges as well, I think he mentioned 1 wire needed power that is normally grounded in the diesel or vice verse. Check out his thread in the conversion section.

I'm very interested in your outcome because I plan on putting a 12V into my 99 V10 and I have a 98 12v PCM and 97 12V Wiring harness. I was hoping it'd be plug and play.
 
I'll have to check his thread out thanks. I'm using all the v10 wiring except the engine harness so I'd assume the power distribution to the dash is correct but I'll pull the diagram and make sure its right. I'll make sure to make a final list of what was needed when I get it all figured out.
 
bikeluver43 said:
Part of me wonders if swapping the V10 PCM back in and plugging the diesel wiring harness into it would make it work?
Click to expand...

Doing that I don't get the no bus error but the tach signal isn't right so tach don't work still. I checked into cumminsboys thread, no real mention on which wire he was talking about but according to the diagram I pulled off shopkey I have all the power and grounds in correct places at the cluster connectors. The matching cluster to the pcm should show tomorrow, fingers crossed my bus issue goes away.
 
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