Dash wiring harness compatibility

[Jnull]

Hi guys new here, mopar man I miss seeing you on CF!

 

Im hoping to get a question answered that isn’t getting much traction on CF. I have a 98.5 24v a friend begged me to take off his hands as it’s pretty modified and a lot of poor work done to it. It’s ppumped, has an external voltage regulator wired up and every light on the truck inside and out quickly pulses, WTS light doesn’t come on, gauge cluster works intermittently, fass is wired to an always hot toggle switch, etc...

 

Im swapping out the entire dash for one pulled out of a 99 1500 and I’m hoping to use the 99+ headlight/fog light switch and move the airbag selector up to the 99+ spot.

 

Would a 99 diesel dash wiring harness be a plug and play direct swap into my 98.5? I believe the only change is the headlight switch, from looking at the 98.5 and 99 Airbag selectors they appear to have the same plugs on the back and the only difference appears to be the shape of the housing since they mount in different locations. Any help would be appreciated.

[Dieselfuture]

I don't think too many here know much about ppump conversions. @TFaoro was one of few that did, but hasn't been here in a while. There are few other guys that knew more that I haven't seen in sometime ether. Guessing all your lights are going nuts because ECM is not seeing vp signals and sounds like they cut some corners on throwing that truck together. It shouldn't need much to run since it's controlled mechanically now, I know there are few things that will no longer work correctly with the conversion, just don't remember what.

[Jnull]

1 minute ago, Dieselfuture said:

I don't think too many here know much about ppump conversions. @TFaoro was one of few that did, but hasn't been here in a while. There are few other guys that knew more that I haven't seen in sometime ether. Guessing all your lights are going nuts because ECM is not seeing vp signals and sounds like they cut some corners on throwing that truck together. It shouldn't need much to run since it's controlled mechanically now, I know there are few things that will no longer work correctly with the conversion, just don't remember what.

I don’t need any help in regards to the ppump conversion, and I’m sure most of the issues I’m having are ecm related. I can figure those things out.

 

What I’m after is finding out if a 99 dash harness is a plug and play swap into a 98.5 while obviously using the 99 headlight switch.

 

Whats the pcm mod in your signature if you don’t mind sharing?

[Mopar1973Man]

ECM and PCM are both fried. Start with sending them both out for repair. Then pull the entire harness out and send it to Auto Computer Specialist and they do full wiring harness repairs. The external regulator is a sign you fried the blue wire with a short fried the PCM voltage regulator. I do have a fix to prevent that. Then as for the ECM you need to do a new alternator and the W-T ground wire mod. This will protect the ECM from frying. You WTS light issues stems from excessive AC noise and burned the ECM up. So all you did to remove the VP44 because of electronics you still got shot in the foot. I still recommend to ditch the P-pump and return to a VP44 becuase they have way better street manners. Way better diagnostics and power to be made vs a static timed pump. Still in all you nedd ECM, PCM and the wiring fixed. All came be done through Auto Computer Specialist.

 

 

The VP44 world we can make some serious power with the Quadzilla and VP44 pumps. No smoke and all pure power. I'm roughly 500 HP and leaving 3rd gear with stock fuel (Quad Timing only Level 2) I can break the tires loose in the 3rd on dry pavement. Still little low in MPG but 18 to 19 MPG is shabby. Got a new idea for a new fuel map.

 

When your tuning from your phone vs a tool box... Something a p-pump cant do without HOUR of tool time and setting plunger lift but still no dynamic timing. I typically cruise at 19° t o 21° at 2,000 RPM. 

 

Edited January 6, 2021 by Mopar1973Man

[Dieselfuture]

15 hours ago, Jnull said:

Whats the pcm mod in your signature if you don’t mind sharing?

It's what @Mopar1973Man said, a fuse on a charge wire from alternator to pcm. There is an article here somewhere. In case alternator shorts out it will blow the fuse instead of pcm. WT is a very good mood that doesn't cost much and improves electrical stuff on our trucks.

[Jnull]

41 minutes ago, Dieselfuture said:

It's what @Mopar1973Man said, a fuse on a charge wire from alternator to pcm. There is an article here somewhere. In case alternator shorts out it will blow the fuse instead of pcm. WT is a very good mood that doesn't cost much and improves electrical stuff on our trucks.

I’ll have to look the pcm mod up thanks. I’ve had the WT ground mod page on here saved for a while, definitely something I’ll be doing.

6 hours ago, Mopar1973Man said:

ECM and PCM are both fried. Start with sending them both out for repair. Then pull the entire harness out and send it to Auto Computer Specialist and they do full wiring harness repairs. The external regulator is a sign you fried the blue wire with a short fried the PCM voltage regulator. I do have a fix to prevent that. Then as for the ECM you need to do a new alternator and the W-T ground wire mod. This will protect the ECM from frying. You WTS light issues stems from excessive AC noise and burned the ECM up. So all you did to remove the VP44 because of electronics you still got shot in the foot. I still recommend to ditch the P-pump and return to a VP44 becuase they have way better street manners. Way better diagnostics and power to be made vs a static timed pump. Still in all you nedd ECM, PCM and the wiring fixed. All came be done through Auto Computer Specialist.

 

 

The VP44 world we can make some serious power with the Quadzilla and VP44 pumps. No smoke and all pure power. I'm roughly 500 HP and leaving 3rd gear with stock fuel (Quad Timing only Level 2) I can break the tires loose in the 3rd on dry pavement. Still little low in MPG but 18 to 19 MPG is shabby. Got a new idea for a new fuel map.

 

When your tuning from your phone vs a tool box... Something a p-pump cant do without HOUR of tool time and setting plunger lift but still no dynamic timing. I typically cruise at 19° t o 21° at 2,000 RPM. 

 

Thanks for chiming in Mike. I didn’t do any of the work to this truck, the way it sits is the way I received it ppump and all unfortunately. I wanted nothing to do with it but a good friend literally begged me to take it off his hands for a price I couldn’t pass up.

 

I like VP44 powered trucks, my 99 with the quadzilla was a great truck when it was on the road but since I didn’t do the ppump conversion on this truck I don’t have any of the removed parts and won’t be tracking them down to swap it back. I’m not going for all out power just a small set of compounds and probably afc live for tunability.

 

Youre saying I need to send the entire engine wiring harness into be repaired?

 

Also do you have any input on my original question about 98.5 and 99 dash wiring harness compatibility? Thanks.

[Dieselfuture]

2 hours ago, Jnull said:

Also do you have any input on my original question about 98.5 and 99 dash wiring harness compatibility? Thanks.

I don't sorry

[Jnull]

10 minutes ago, Dieselfuture said:

I don't sorry

Hahaha touche

[Jnull]

Bump for anyone that can help with 98.5 and 99 dash wiring harness compatibility.

[dripley]

I have no personal experience but Dodge tweaked alot of stuff that would cause issues from 2000 to 2002 where they want work. 98.5 to 99 I would not know.

most of the harnesses I see on my 02 have tags with part numbers for what thats worth.

Edited January 9, 2021 by dripley

[Jnull]

2 hours ago, dripley said:

I have no personal experience but Dodge tweaked alot of stuff that would cause issues from 2000 to 2002 where they want work. 98.5 to 99 I would not know.

most of the harnesses I see on my 02 have tags with part numbers for what thats worth.

00 and up definitely wouldn’t be compatible with 99 and down, im not even sure 01 and 02 are compatible on everything. You’re definitely right in saying a lot of goofy stuff went on.

 

the biggest difference is the headlight switch and overhead console, I’m not sure if the overhead console wiring ties into the dash wiring harness or not.

 

Since I’m swapping an entire half ton dash in I have to swap dash wiring harnesses anyhow, so I’m hoping to swap a 99 harness in instead since the one in my 98.5 is hacked up some. I know you can rewire the headlight switch to take the 99+ style but it seems like they should be compatible, that’s a complete guess tho lol.

 

Your truck sounds awesome man, 02 6spd long bed...very desirable.

Edited January 9, 2021 by Jnull

[dripley]

I am rather fond of the truck. It has presented with some challenges over the years but has still treated me rather well over the years and I believe it has many more left for me to enjoy. 

 

I would also wonder how much the 1/2 ton gasser vs the 3/4 ton w/Cummins differs. A lot of unknowns for an electrical neophyte such as myself. 

[Jnull]

3 hours ago, dripley said:

I am rather fond of the truck. It has presented with some challenges over the years but has still treated me rather well over the years and I believe it has many more left for me to enjoy. 

 

I would also wonder how much the 1/2 ton gasser vs the 3/4 ton w/Cummins differs. A lot of unknowns for an electrical neophyte such as myself. 

I bet man.

 

I wasn’t planning on using the half ton harness. No way would it work in a diesel truck. I’d source once from a 99 diesel.

[dripley]

1 hour ago, Jnull said:

 

 

I wasn’t planning on using the half ton harness. No way would it work in a diesel truck. I’d source once from a 99 diesel.

I assumed you were trying the 1/2 ton harness since that where the dash came from. 

[Jnull]

9 minutes ago, dripley said:

I assumed you were trying the 1/2 ton harness since that where the dash came from. 

Nah I’d find a diesel one. I just hope someone can answer my question!

[Great work!]

I changed my cab because of rust the doner was a crashed 1500 one year newer. Nothing was the same even the door connectors were different because of the optional radio. Swapped all wiring including the taillight harness and added cab lights.

[Jnull]

17 minutes ago, Great work! said:

I changed my cab because of rust the doner was a crashed 1500 one year newer. Nothing was the same even the door connectors were different because of the optional radio. Swapped all wiring including the taillight harness and added cab lights.

What year was the donor? A lot can change depending on year and options.

[Great work!]

2000

[Jnull]

Bump for anyone that can help answer this.