Minor electrical gremlins

Hi
Enjoying my 85 gti cabby so much it's now my main car. Generally reliable wee car, great heater these colder mornings but couple minor things need sorting:
1. Indicator flasher works when cold but after 10 mins or so, no flash. When working it flashes slow. Getting quite good manually flicking stalk on/off but need to fix. Read elsewhere could be hazard switch or my first thought the flasher relay. So which most likely?
2. No lights on dash. Thought initially dead bulbs but found no output from dash dimmer switch. For quick fix these dark evenings can I bypass dimmer with 12v tapped off headlight feed or is full on less than 12v?
3. Temp gauge reading high all time and red light flashing. Checked 10v stabilizer output and getting 10v and checked resistance of sender as ok but no voltage at sender. Anyone know colour and route of cables to/from dash to help me track issue. Or any other suggestions? Also have no coolant level sensor cable where it should be, so useful to know colour and where they are routed to see where its hiding.
Thanks
John

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I had Gremlins in my wiring, it took me ages to get rid of them (slightly off topic, sorry, I couldn't resist)

Yep now I see the photo they do look familiar …
But how'd do you get rid of the wee bleepers!

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Don't use water, Electricity and Gremlins, don't like water.

1. are the hazards affected by the same issue?

2. yep can do this no problem. alternatively look at the fusebox for a spare grey/blue spade plug on G spade #8, put an ignition or lights on feed into that this will back feed the dash lighting. G spade 1, 2, 3 and 5 are ignition, G spade 9 is a feed from the numberplate light fuse (you have checked the fuse for the dash lighting and plate lights right?)

3. does it still do it with sensor unplugged? find the coolant warning relay 42 or 43 above the fusebox, unplug it see if it stops. check the wirign to the relay socket as well, make sure its not shorted anywhere on the red/yellow and/or blue/yellow

Hi John

Thanks for pointers:
1. believe so - have ordered new relay from vwheritage so will see if that fixes it
2. the plate lights are working - I'll do quick fix for now, then will look at other option later
3. yes, same with unplugged - will check relay as suggested

Cheers
John

1. yeah likely its the relay, but hazard switch is a possibility
2. ok, its probably the dimmer at fault then. sometimes a wiggle is all it needs, or you may have to have a look in the top to make sure the metal prongs on the wheel are clean and make sure they make good contact with the resistor circuit

Thanks John
relay arrived yesterday and now flashing at nice speed rather than slow or full on, so that is sorted - didn't realise how slow the old flaky relay was.
did temp/botch fix for dash lights from switched live from headlight switch so at least can see what speed I'm going in the dark.
Will check wiring properly over weekend, recall when trouble shooting rear lights for MOT, I ended up piggy backing the number plate lights off the rear light (yes another rushed botch!) so could be the fuse after all. Then I'll take a look at the switch

Glad to hear that things are working out for you but I couldn't reset the Gremlin comments.

So here's what we really do suffer with if you live out in the countryside in Austria.







There are not furry cuddly creatures, if fact if you try to cuddle one of these you'll never play a musical instrument again!

They are called "Marder" and they are like our Polecats but wild and larger. They will eat a destroy anything made of rubber or plastic.
Mainly water pipes, brake pipes and tires.

They can be devastating under the bonnet, I had one once got under mine and started to eat the padding on the under side of the bonnet!

Back on subject. ☺️👍🏼

Not that I would ever, ever want to get into any sort of disagreement with Rubjonny over electricity and wiring stuff (cos I know I'd loose!), but (I can't believe I'm about to do this) mine was doing the same, no dash bulbs and engine temp reading high and light flashing all the time and it turned out to be a really bad earth on the back of the cluster.

Sorry

I'll go away now

Sorry

Ian

no disagreement from me, its definitly somethign to check. the earth on the mfa clocks goes to the side of the head, so well worth checkign this wire is good, its the brown/white

Thanks chaps
This isn't first issue I've had and from prior post on main beam indicator issue i did add new earth for cluster
But will double check my handywork to make sure still sound earth

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I had same temp flasher problem s and it was relay 42/3

Grounds are the bane of these critters.

Read my signature.

Rats over hear love to eat the new wiring of the cars as the insulation is made of plastic from plants…

Had one chew on my High voltage leads from my coil pack…. I only wish the engine was running, but I got him in the end,  a good trap and a co2 pellet gun.

Relaying your headlights and starter removes the load off the electrical switches ignition and the lamps, this add to the longevity of them.  My 90's with the air bag are a pain in the rear to get out….

 

Sorry for highjacking but I've got MFA and indicator lights but no back light.

If your regular dash lamps are good, then the issue is usually the bulb on the MFA.

There are only 3 bulbs on the cluster.
Two for the instruments and one for the MFA or clock.

If the MFA isn't working, then that is a Ground wire from the valve cover to the coil bracket usually.

Cheers Brian, MFA is working (except it won't change the time for some reason).
Looking like both lamps must have gone then.
Might leave it for the summer as it's a sod to get back in as the speedo drive is really tight up against the bracket.