Fiat Uno Headlight Problem

On an 88 Uno the earths were below the battery and any leakage could corrode them. One fault of poor earth was that both left and right direction indicators would flash at once.

I 'think' the Headlights work through the Ignition switch, and that the contacts in there sometimes corrode/break down, so you might like to check there too. I've heard that you can get a heavier duty switch. Someone else may verify this ?

Graham

I was following a Fiat Punto that was doing that once, except one indicator (i.e. the one that should be flashing) flashed slightly brighter than the other one.

-- James

I can confirm that the headlight and tail light current (which is quite substantial) goes through the ignition switch, so that the headlights go off wnen the ignition is off. Worse, to this current is added things like heater fan, wipers, rear screen heater - all of which push up the amps. The push on quarter in tab carrying this load, not to mention the ignition switch itself starts to cook and the switch block on the end of the ignition switch turns brown and starts to char. Both Mk1 and Mk2 Unos are prone to this, particularly if you drive mostly at night, when everything is on.

Having had total failure on the motorway in conditions that needed wipers and heater I was not well pleased when all the lights etc went out. Not to mention this could be lethal if there was a HGV on your tail.

It's not a roadside fix, you need to get the steering wheel shroud off, plus have a replacement switch to hand. With a bit of luck you may be able to swap just the contact block. Replacing the ignition switch is a pain in the arse due to it being fixed with break head bolts. I can't imagine why, no joy rider is going to the trouble of removing it.

Lets hope you only have an earthing problem. You might also check the fuses and fuse box.

Thats interesting to know, at least I now know I'm not looking for a relay hidden somewhere inacessible. I had also considered it could be a problem with the the headlamp stalk itself, but I couldn't see why a problem with that switch would take out everything, including main beam and flash etc.

The car is the girlfriends, and she has a tendancy to leave the lights on and turn everything off at the ignition, then restart the car in the same way. I can't see that being helpful in this situation. This actually explains something odd I found when I was trying to fix it - I'd turn the car off, check the fuses, nothing would be wrong, I'd turn the ignition on again, and it would work again - it looks like the switch. I assume that not fitting a relay in this circuit was a cost option for fiat.

Anyway, Nothing will be done to it till the weekend then its grab the DVM and then, recheck the fuses and then check the earths. Then if no joy remove the steering shroud to check the ignition switch and the condition of the connectors.

Luckily it's parked outside her house, so there not a problem in working on the car, unluckily she's got mine to drive round in whilst her's can't be driven (don't ask how that happened).

Anyway, thanks for the info, I'll let you know what happens...........

Mark

If I could add my 2p worth...............

I had a similar problem with an Uno 45 where the headlight main beam would work fine one minute and fail totally the next.

Replacing fuses etc had no effect.

I eventually traced the fault to the fuse board itself - I discovered that waggling the connector blocks to the board miraculously made them work again.

Tracked one down at a scrapyard, swapped it and it's been fine ever since. (touch wood etc. etc.)

I took the old board to pieces and examined it but there was nothing to see visually. Possibly a fractured printed circuit track?

HTH

Paul

IME, things like this go where the solder meets the contacts on the back of the fuse holder.

They _appear_ to be OK, but sometimes there'll be a tiny black line between the solder and contact.

This is called a Dry Joint.

Normally getting a soldering iron and going through all the solder, melting it, causing it to re-attach to the connector is enough.

Pete.

Having blown two headlamps that way I remember to turn the headlamps off before starting.

Also around town the headlamps are more for other vehicles to see, and I have gone down to non-halogen ones which do use a lot less current. I do not think they dazzle oncoming drivers so much, either. Then, too, I think the battery will stay in better condition, as the current drain to halogen lamps must reduce the voltage to charge the battery in mainly night driving.

Yup. At least having many of them in the same accessible place made fixing easy.

The headlights are now fixed, it wasn't the ignition switch, but a connector under the steering column shroud, to the right hand side of the dash.

This connector had white plastic cover which was burnt and brittle.

I removed the plastic cover and cleaned up the spade connectors with some wet and dry, then insulated with masking tape. Everything now looks to be fine.

Thanks for all the help and advice

Cheers

Mark Garner

In alt.autos.fiat Mark Garner wrote: : Hi

: I have a problem with the headlights on a 1994 Fiat Uno 45 ie SX

Contact problem inside the fuse box. (or the grounings.)

My mom used to do that, it took a dozen or maybe two headlamps to figure out why they were blowing so often.

Jasper