Author Topic: Rewiring a Dash  (Read 651 times)

Anastasiofan92

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Rewiring a Dash
« on: June 02, 2010, 06:11:44 PM »
All right guys, now that I got my dash harness from Pete (Thanks again) I will do a step by step explanation with pictures (for the most part) of putting a dash harness in. This is going to be my first go around with one of these bad boys, but I am going to do the best I can do get this done myself...

Here is your standard dash harness





On the Harness you'll see a LOT of wires, and this snake-like apparatus is what controls every single electrical circuit you operate inside your car... The stem of the harness is your fuse block.. This block (pictured below)





Contains the following circuits:
A Flasher on the top left of the block which controls (to my knowledge) the hazard flashing unit.

To the Right of the Flasher a 20 Amp Fuse which controls Directional Turn Signals and Back Up

Below the Flasher we see a Fuse that looks like this (40 Amp I believe)




This fuse protects the power/accessory circuit on your block.


The fuse to the right is a 10 Amp Fuse that protects the gauges and 'trans'.

2 Slots below the flasher is the fuse for the clock and courtesy circuits. It is a 20 Amp fuse.

To the right of the Courtesy and Clock fuse we have a 25 amp fuse for the heated rear glass, I don't have this option in my car, but for those of you who do you need to replace this fuse..


Three slots below the flasher we have the Tail fuse which is 20 Amps.

To the right of that we have a 25 amp fuse for the heater and A/C control unit..

Four slots below the flasher, we have the fuse for the stop lights and hazards, 20 Amp

To the right of that fuse, we have a 10 Amp fuse for the radio.

Also, below the stop light, we have a 4 amp fuse which controls the instrument lamps.

To the right of the instrument lamp fuse we've got a 25 amp fuse which controls the wiper control..



If you're keeping score this is what you've got

Four 20 Amp Fuses

One 4 amp fuse

Two 10 amp fuses

Three 25 amp fuses (Four if you've got heated rear glass)

Do yourself a favor, replace ALL of these 30 year old fuses when you decide to replace your harness with a new one.



Also, be sure to replace your hazard flasher with a new one right away so as to protect yourself from a potential future problem..







Moving up the harness, I'd like to touch on a couple of other things that you might want to tackle now before working on installing your new dash harness. First of all, the turn signal flasher.. Yes I already mentioned the hazard flasher, but it's a different unit..

The Turn signal flasher you'll find connected by way of a two prong slanted plug at the end of two wires about six inches or so above the fuse block. These wires and flasher unit work together to trigger your turn signals on the parking lamps in front of the car, the marker lights on the side, and the tail lights in the rear...

When installing a new-old harness, I highly recommend you replace this flasher unit now before installing the harness.. This piece can be a pain to work on when the harness is installed, so it's best to replace it now and leave the potential problems that may present themselves, in the dust.

Here's a picture of what I'm talking about






Moving on. If you look an inch behind the flasher you will notice a white box looking thing (Technical wording).
This box is actually a relay that controls your horn. The part number is 344813, and is another item to add to my list of recommended replacements. Do yourself a favor and replace these flashers and relay before you install the harness.. You'll save yourself a ton of headaches...


Moving on..  The next couple items on my immediate replacement list for new old harnesses are bulbs. Throughout your dash harness and especially in your gauge clusters (If you run stock gauges) you will have bulbs that are guaranteed to have been burnt out long before you got the harness. I recommend you take the time now, while the harness is out of the car to replace these bulbs now.. of course after you replace them, you'll need to be gentle in moving the harness around so as not to crack the bulbs, but you get the point..

If you have a deluxe lighting group (like me) you will have several extra lights included in your harness that standard harnesses didn't have. For instance: you will have two kick panel lights that are triggered to come on when the door is opened.. You will also have a bulb in your glove box, pretty cool huh?

The bulb numbers you need for replacing your dash harness are ONE 1891, Two 197's for the kick panels and one of these which I will identify sometime later today..




In case you are wondering most all of the bulbs in your standard gauge cluster are 194's. If you wanted to replace any of those with LED's now is the time to do it before we dive much deeper..


I'd now like to identify some of the connectors on your harness that are probably pretty puzzling at first glance...

First and formost of course is our fuse block, the king daddy of the whole operation.. This bad boy mounts right up to the firewall behind your emergency brake pedal.

This fuse block should be held on by approximately two bolts. The way this thing works, is that the deeper half of the fuseblock actually exits the inside of the car and protrudes the engine compartment below the power brake booster and master cylinder. The two semi circular connections shown here



are what bring the electrical systems in the engine (the engine harness and forward lamp harness) into harmony with the dash harness (Mission Control). Before you begin your installation in any capacity it would be a good idea to take this time to clean out your outer fuse block (the part that connects to the engine and forward lamp harness. Although we will be using di-electric grease when connecting the three harnesses, you need to remove all the gunk and build up your harness has acquired over the years to provide the best connectivity possible...


I think a Q Tip will work well here so give that a try, just don't shoot anything into the holes, except for maybe some canned air if that will work for you...




I'm going to head to the parts store soon and get some parts "fuses, bulbs, flashers and a relay" but I'll be back with more pictures and more advice...





« Last Edit: June 03, 2010, 12:35:10 AM by Anastasiofan92 »

BlkBird

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Re: Rewiring a Dash
« Reply #1 on: June 17, 2010, 03:57:45 PM »
So far this is a good write up, take your time with it and we'll probably add it to the tech section when you're done.

LeighP

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Re: Rewiring a Dash
« Reply #2 on: June 22, 2010, 10:18:35 AM »
Very detailed write up.....excellent reference.  8)
Regards,
Leigh

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Anastasiofan92

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Re: Rewiring a Dash
« Reply #3 on: July 08, 2010, 04:27:38 AM »
Very detailed write up.....excellent reference.  8)

Thanks guys, I've got the dash loosened up. I'll take pictures of what I do as soon as I have the time. I've been real busy with a whole bunch of stuff. We moved two weeks ago and I'm working 40 hours a week now including most weekends so it's been hard to squeeze in time for the old girl...

Anastasiofan92

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Re: Rewiring a Dash
« Reply #4 on: July 31, 2010, 05:13:38 AM »
Ok guys just to let you all know next day I get a day off from work I will continue with this article in the same detailed manner as I started. I've made big headway since we last left off, but the write-up will continue.

BlkBird

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Re: Rewiring a Dash
« Reply #5 on: August 01, 2010, 12:17:44 AM »
Good deal.