Complete rewire, using Painless Universal harness???

[aldad138]

Have any of you fine people done a complete rewire, pulling essentially all the wiring, fuse box, relay boxes and rewired?  As I work on the "big things" like making her stop, turn and go forwards...I find the ability to safely and joyfully drive the car is hampered by electrical gremlins of epic proportions.  Turn signals work, or not.  Windows...reverse lights... clock, volt meter, log lights...wipers...all work, or not on their own schedule.  I know there are shorts, and obvious failures.  There are DOZENS of terminals just left unconnected from the capricious past of the car- random wires coming from or going, nowhere.

Instead of trying to solve each issue separately, my thinking is a modern new harness, new fuses box, relays...anyone with past history?  If not Painless, any other ideas for a good harness and "all in one" setup?

Alex

[WestonE]

Sorry a universal harness will not do it. However replacing earth wires with new ones going to clean connections and replacing corroded terminals in the AMP connectors can give miraculous improvements. Also wire brush the contacts for the fuses and squeeze them so they hold the fuses tight. In this country we can buy a wiring kit with the AMP connectors and a top quality crimp tool from Vehicle wiring products.

If you want to remake loom sections do the engine bay ones first as they fail first.

You can add a relay to the top speed wiper feed and get full speed wiper and add relays to the electric windows to speed them up. Most problems will be bad earth an or bad connections, but obviously burnt or rigid wires from heat should be replaced.

It is best to remove the loom section and spend a relaxing evening or 2 working through it 1 wire at a time..

Eric

[mangocrazy]

Is there any benefit to be gained by going up one gauge on the wire size, Eric? It strikes me that a lot of the wire sizes were very marginal for the job they had to do in a hot engine bay.

[HFStuart]

If you use modern thinwall wiring of the same overall size this will happen anyway.

It's likely to be a marginal benefit on higher current draws and earths.

[aldad138]

Thanks Weston.  When I contacted Painless, they had a similar answer that the universal harness they have, would require significant customization to go in.  So, I guess I go one at a time.  Right now, the rear lights are totally failed so I will start there, grounds, terminals and check for obvious damage to wiring.  Then, the fuse box like you recommended.  Any advice on what to do with all the disconnected stuff, under the dash, in the engine bay and trunk?

Alex

[WestonE]

Alex

On the disconnected terminals electrical tape over the end then round the tape will prevent any risk of a short by accidental contact. Only remove things if you have studied the whole circuit on a wiring diagram and you understand what else is connected.

PS adding local direct earth to things like lights can help as the OE design can involve long runs through multiple connections to get to earth.

Get used to checking what happens with a good battery earth connection in place of the corroded one. If you have clean power and earth to consumers like lights they work so start from the problem consumer and work back checking the wiring diagram as needed.

Good Luck Eric

[thecolonel]

I suggest you check loom
where it runs along the sill,
A few times I've come across
damage caused by a small
amount of welding.