The "brown wire fix"

[cooter131]

Hello again,

I guess the following problem is common to many FIAT owners:
The headlights are some how dim, the heater fan is turning slower than normal and the more circuits you switch on the more the temperature and fuel gauges rise.

I have experienced this twice (both my 1300 and my 1600 131s). There are some suggestions about the so-called brown wire that connects the starter solenoid with the ignition switch and the battery positive.

Info obtained from this usefl link:
http://flumichigan.italiancarclub.com/TechArticles/Brown%20Wire%20Surgery.pdf

Has anyone tried replacing it and are there any results?   
Grounds also appear to be a common issue but I have already checked those and there is no voltage drop across their terminals.

Any thoughts welcome...

George K

[david]

I did mention this before but cant remember on what thread but if there is any sign of heat or burning where the brown charge wire connects to the ignition switch you need to remove this wire from the plug at both sides cut back and solder it together using an old type soldering iron that you heat up on the gas and this will solve the burning at this point and as I mentioned previously I nearly had a 131 sport catch light because of this wire but It does not solve the dim headlight problem, that is because there is a voltage drop to 10 volts by the time it reaches the headlight bulb !  so you need a feed from battery to relay & then to headlamps & then use original headlamp wire as trip to relay to light headlamp and this will solve problem

[cooter131]

David thanks!

I have already compensated the low voltage on the headlights by installing a new power cable from the battery to the headlights main switch. The voltage drop in my case was somewhere between this section and thus I now have 12V at the bulbs.

I will try the brown wire fix tomorrow and hope this will fix much of the rest. (wipers' speed-heater fan-gauges etc.)
A couple of weeks before I removed the fusebox, had the contacts cleaned, installed new fuses and put it back but the problem was not solved. That is why I now focus on the steering column harness.

It is going to be a straight forward job as I have the fresh cable supplying 12V nearby (at the headlights switch) from the previous modification. 

[106usj]

I have the exact same problem with the lights and wipers.
 Wipers improved slightly when i renewed all the fuses but still slow.
I will fix when i get round to it.
Thanks also for the info.

[paulcas]

if it helps, came across this on another forum site covering the "brown wire fix"


http://www.mirafiori.com/faq/content/bwfix/bwfix.htm

[mirafioriman]

Interesting article.....

Perhaps a good long term solution would be to use this live that goes to the ignition switch as a trigger for a relay. Then wire in a new live from the battery through the relay to the output destination with a decent thickness of brown wire.

This should stop the problem of the ignition switch terminal burning itself into oblivion.

[mirafioriman]

Another thing comes to mind.

Once I have broken down in my 131. It simply refused to start after work one day. I called out the breakdown cover as it came free with my insurance The mechanic who came gamely tried but could not get it to start. I suggested the ignition switch which he dismissed.

After he A framed the car home for me I fiddled on and guess what? A replacement ignition switch solved the problem and she ran again! I guess the brown wire issue had occured?

[miro-1980]

Now when I think about it I had the same problem

The ignition switch just failed me one day before I left the garage for my racing weekend. I replaced it from one i juts got from Yagmur ( thank you Yagmur again).

I still have it in my garage and when I get a chance i will inspect it closely for symptoms of the brown wire problem.

Will report findings

Miro

[cooter131]

Some feedback:

In my case the connector behind the sterering wheel was in very condition.
The originally installed brown wire was replaced but unforunately the results were not the expected.
The wipers' speed was somehow increased but not as it should be.
Still the water temp and fuel gauges readings increase as more circuits switch on...


There should be some voltage leakage. (somewhere )

Concerning the ignition switch discussion it seems to be really a good or no good situation.
It either works and turns the engine or it simply doesn't.
I do not know whether the voltage drop can be caused by the switch itself.