Indicators blinking slow

Hi all,
On my MK2 the indicators are blinking very slow and I also have the idea the bulbs don't even go on fully. There is no proper on and off time, they just sinus up and down.
I've tried some led bulbs but that doesn't help.

My cousin hinted it could be the relay. Is that a common issue? Would a new relay solve this or is there a higher chance it's in the wiring?

The issue is on all 6 of the indicators and the ground connection (especially in the front) is good.

 

My first call would have been earths but you’ve checked that. Definitely try another relay first.

 

To confirm, is it just the indicators? - Are any other lights/circuits dim or acting up?
If the answer is no, then I agree with Phil; try another relay, as the relay contacts may have become damp/oxidized.
There might be no harm in confirming that the battery/alternator is behaving properly as well.

 

If it was earth I also would expect a slightly different performance between the lights (for instance, LHS lights are earthed on the original battery earth point 20cm away. On the RHS the mass is much further away (I think it is near the relay box on the LHS).

Having said that, wires to the indicators are fed double (so + and -), but I'd have to check that to be sure.
A new relay isn't really expensive, so worth a try. It could well be 38 years old.

 

Which relay is it? I have a few genuine ones knocking about.

 

Relay no 21.

 

Received the new relay earlier this week and built it in.
It looks like there is not much of a change, I suspect the wiring to be an issue (especially in the front).

When I replace the front bulbs for LEDS, the LED also shows a slow sinusaal signal and doesn't come fully on.
But somehow, when I replace the rear ones as well, it is better. Both front and rear LEDs go on fully and turn on an shut off directly, without glowing.
With the old relay and 2 LEDs fitted, the relay goes crazy, buzzing and no light. The new relay handles it better.
As everybody knows, LEDs have a lower resistance causing the blinking to go faster. This is for indicating as well as hazard-lights, but as the light is brighter I don't care. It's more clear to other track users!

 

You can buy LED specific Indicator Relays to bring the flashing speed back to normal.

 

You're right, Amazon has one which I could find easily

Well, as said it doesn't bother me (jet), looks like I'm in a hurry and I am

 

I have just ordered a relay from here Classic Car LEDs Ltd They list one for Mk2 Golf. I am wondering whether to use white or amber leds, what are you using?

 

White on the front, amber in the back. Mind you I don't have original light units. Originally the glass is coloured afaik.