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TR6 71 TR6 Rewiring project

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hondo402000

hondo402000

Darth Vader
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Well I have the new harness all hooked up, I felt confident that all is or was hooked up correctly, some things were missing and I think I got everything on the proper connector, the question would be once I have everything hooked up, is there a way to check with an amp meter before hooking the battery up and frying the new harness, Right now if I checked resistance on the brown wires I get resistance, shouldnt there be none unless a switch is in the on position. I have Dan Masters book but it really doesnt tell how to check a new harness before hooking up the battery

any direction would be helpful

Hondo
 
When I rewired my Bugeye last year, I substituted a 9 volt battery (as used in smoke detectors) for the car battery. In addition, I installed a 5 amp fuse in line with the battery. Then I turned on each device, one at a time, just momentarily (9 volt battery won't last long) and I monitored the current (multi-function VOM meter). As a result I was confident that there were no major mistakes, and that I wasn't going to smoke the harness. I was this extra carful, because I added 6 fuses and three relays, and had to dice and slice the new harness. Good luck.
Scott in CA.
 
Well I did find out one thing
I went back and pulled all fuses, so I get no continuity reading from and brown wires or white wires

how ever if I touch ground with one lead and a lead to the red wires comming off the fuse block I get continuity readings. But since the red wires all go to the instrument pannel lights and parking lights shouldnt that be correct?

I also get continuity by touching a ground and the green wires at the fuse block

green wire go to wiper motors, blower motor, voltage stabilizer, temp and fuel gauge brake lights hazzard switch, and some have lights to them

Hondo
 
Yes, those are both correct Hondo. Your continuity checker can't tell the difference between a short and a legitimate load like a light or gauge.

My suggestion would be to take an old headlight bulb (or a new one if that is all you have), and temporarily wire it in series between the battery and the car. It won't pass more than about 5 amps, and for small loads (like the gauges) the brightness of the bulb will indicate whether you have a direct short or just the normal load. That is better than using an ammeter IMO, at least initially, because most ammeters can be damaged (or a fuse blown) by a short. The bulb will just light up.

I keep a pile of old headlight bulbs for just this reason; generally only the low beam filament is burned out so I can still use the high beam for testing of various sorts.

For larger loads (like the headlights), you can use either several bulbs in parallel, or a circuit breaker. The type of circuit breaker that fits in place of a glass fuse is handy to have, so you might want to just pick up a couple to have as spares.
https://www.rockauto.com/catalog/raframec...42-85617-780029
 
Not sure how the TR is wired, if it uses fuses for the lights, which the Bugeye does not. One would expect to get continuity with lights down stream, as they will draw current, unlike the items switched by the key. The thing to verify, which I did, is to check if the current draw is proper for the device and switches on and off. One can also get a WAG by how much of a spark you get!
Scott in CA
 
One can use the spark method. With everything off, and all the fuses out, if when you just brush the last battery connection to the battery, you get just a small spark, that is good. Leave the battery connection off, and insert one fuse, then try the battery connection again. Continue until all the fuses are installed. Then start turning one thing on at a time and repeat the battery cable against the terminal. Now the sparks will be bigger, and it will allow you to check if the devices all work. Many different methods, the headlight one works, or a relay, just take your time, and don't blindly hook up the battery connection and turn the key.
Scott in CA
 
well when I pulled the old harness out I cut the wires that were attached to the ignition, relays, switches, etc, so at least I would have some reference of what color wires went where the drawing is clear and straight forward but I cannot assume that I didnt get something mixed up. like if you look at the wiper switch in the drawing all 4 connections show in a row but the switch has 4 connections but 2 on the left and 2 on the right, and also are the connections on the drawing referenced looking at the back of the switch or the front, so all the above sound like good ways to hook up the battery and slowly check circuits

Hondo
 
well I put the battery in the car, its really low on charge but I figure thats good, so far, the glove box light works(previously there was not one), the running lights work, the tunnel lamp works but only when you turn it on at the light, got to go over the door switches. the light at the IG switch works(hooked it thru a togle switch) when I turn the IG on the wiper motor runs but in all positions so need to check that out. I am sure the wires on the switch are mixed up somewhere.

the hazards dont work(didnt have hazards before so I will have to sort that out and have nothing to go by) but not sure if its the hazard flasher is bad, I didnt replace it, and the turn signals dont work but also could be the battery is too low and I must get another flasher unit just to be sure.

hondo
 
Hondo , hook it up to your battery charger. That's how I tested my Master's Panel
 
I got the battery charging now, but I have everything hooked up, excpept the head lighs, and they are on relays so all I have to do is run a hot from the battery, but eveything works, even got the hazards working too. but that hazard rocker switch is giving me some issues, since they are NLS I am looking for a subsitiute rocker switch that would look some what correct and replace the oldy one, I have cleaned it several times and just cannot figure out why it wont work, its really simple on the inside, but all is well and so shorts either, next is getting the new transmission tunnel ready to go in, glue the carpet padding on it and drill the holes for the bulk head bolts

Hondo
 
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