Hey,

My brother recently bought a 91 RS and shortly after he got it the speedometer stopped working. I took it to a garage and the mechanic told me the wiring under the dash is a mess and I would be better off just replacing the whole harness under the dash but a new one would cost between $1500-$2000... or I could take the whole dash and wiring out of the 91 I found in the JY.

Are there any write ups for replacing the dash/wiring around here or on the net? I almost got it out today but the yard closed before I could finish. I'm not a mechanic but I think I can do it, I just could use some advice. Is it difficult to get all the wiring out?

Thanks in advance!

 

Yes it is a pain to get the entire harness out, best way is to leave it attached to the dashboard and pull it all together.


Can you get us some pictures of the wiring that supposedly is so bad that the entire harness needs replacing ? I'd hate to see you go through a lot of unneeded work for someone elses bad diagnosis.

 

It looks bad to me and I know someone put a sound system in the car at one point and maybe tried to put in a security system but failed. It's all very messy. The one in the JY has the whole dash and is very clean. If I can get it out, I know I can get it back in. I'm just not sure about where all the main connections are. I'm sure I can figure it out though.

I can take some pics at some point tomorrow.

Thanks!

 

The main disconnect points are the C100 which is the bulkhead connector by the brake booster, first you have to remove the bolt in the center of it which is 1/4" or 7mm, then the engine side of it will be able to be pulled away then there are two nuts that hold the body half to the firewall, iirc they're 10 or 11mm, then you can pull the chassis side of the connector in, then unplug all of the connections to the pedals, steering column, etc, and then on the passenger side of the dash underneath you'll find the c207 underdash connector its pretty simple to unplug, you'll also find a connector seperating the chassis harness from the taillight section along the drivers side of the harness.

Thats the main rundown, you'll find little grounds here and there and other simple stuff.

For everything to work right if its a TBI car it will have to be a TBI chassis harness, TPI and V6 cars use the same chassis harness.

 

TBI, TPI? The one in the JY is a V6, same as the one I'm fixing so I'm thinking they should be the same.

Thanks so much for the advice!

 

TBI - Throttle Body Fuel Injection
TPI - Tune Port Fuel Injection

I looked it up. I believe min is TPI and I believe the donor car is too so hopefully everything will work.

 

Does the center console need to come out in order to remove the dash?

 

it makes it alot easier to remove the dash if the center console is removed first.

 

Yes, should only take a couple minutes to remove the center console.

I would go ahead and start by removing the seats, console, steering column, and carpet, then proceed.

 

Yes, these things are definitely have to come out to get out the dash!
(Except the steering colulm. I was able to get out the dash without taking that all the way out)

What a pain in the a$$ that was. I really figured there would be more connections so you didn't have to take out all wiring in the chasis. The door wiring was particularly annoying. I think I may add connections at the doors because I don't really want to try to feed them thru the door again.

 

Under $100 for the whole dash and wiring. Not too bad I must say. A whole lot less than $1500. I'm a little nervous about doing the swap. Hopefully every fits and works when I'm done.

Wish me luck!

 

You really shouldnt have to be taking wiring in and out of the doors often at all, chances are anything you add is likely to cause more trouble than good, I'd recommed against hacking the factory wiring, that you are replacing because of previous hacking as it is...

 

I wouldn't call it hacking exactly. I'm not trying to extensively modify the wiring, I just want to splice in some connectors to make it easier. I think it would take less time then running the wires thru the doors again. Idk, I'll think about it.

Thanks for the advice.

 

That's what it looked like. You can see the security system box someone tried to install in the background.



I got the dash out today and I realized the wiring doesn't need to come out of the doors which is a big relief.

 

There was some extra stuff under the hood too. I removed most of it but there's an extra ground added to this connector. I'm not sure if it's a problem or not. Thoughts anyone?



Sorry, the pic's a little more close-up than I thought.