Dim instrument indicator lights

Tor

Well-Known Member
Both of the ‘arrow’ indicator bulbs in the instruments flash, weakly, when using the indicator stalk in either direction. I’ve just replaced the instrument base unit for a couple of other reasons and hoped it might take care of this, but no. I’ll have a look in the multi pin connectors and the switch itself. Any other places I should look?
 
I’ll check it out, but all external indicators (and other lights) are strong and bright.
 
Have the green plastic pieced that the bulbs shine through gone dark with age? This has happened to the blue on my high beam indicator light. You can only just see it even in the dark!
 
Have the green plastic pieced that the bulbs shine through gone dark with age? This has happened to the blue on my high beam indicator light. You can only just see it even in the dark!
No, with the fascia off, the bulbs didn't shine much at all. On both housings. But the main thing is that they're not both supposed to flash unless the hazards are on. Which makes me think, could there be an issue in that circuit..?
 
Disconnect the hazzard flasher unit, if that stops them flashing try a new one.
I seem to recall way back I had an issue with an indicator bulb which had internally shorted and this caused weird things to happen elsewhere.
 
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Tried this now. Disconnecting the hazard disabled the indicators. Tried a backup hazard switch, same as before.

But wait, did you mean the relay?
 
Unplugged the hazard, and tried different flasher units in both hazard and indicator circuits. No change.
 
Tor,
I’m with GRTV8 on this.
I suspect there’s an earthing fault somewhere, possibly up behind the dashboard.
Earthing is the common denominator.
It may be a case of undoing, cleaning and refastening all the earth connections.
Did this fault suddenly appear or has it been intermittently happening?
 
The indicator warning lights are connected to earth on a common pin (11) on the circuit board. If this is not made the warning lights will try to earth through each other and will have 6V on each giving the exact symptom's described ie both flashing dimly together . I am sure it is a poor earth on the board.
 

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Did this fault suddenly appear or has it been intermittently happening?
It’s been like this since I got the car in 2009.
The indicator warning lights are connected to earth on a common pin (11) on the circuit board. If this is not made the warning lights will try to earth through each other and will have 6V on each giving the exact symptom's described ie both flashing dimly together . I am sure it is a poor earth on the board.
Then it should be in the loom as I’ve replaced the board to no avail. I’ll try to earth the pin separately to see.
 
Tor,
If all the external indicator lights work correctly with both the hazard lights and the indicator stalk, that implies to me (I’m happy to be corrected if wrong) that the wiring loom is sound and the issue is within the circuit in the dashboard to the ‘green arrow’ light globes.

Are there any issues with the side lights, tail lights or reverse lights operating incorrectly when the indicator globes are flashing?
 
Are the bulbs new? If they are originals, by now they are likely mirrored with evaporated tungsten which will make them very dim.

Yours
Vern
 
IMHO as any cars get older the quality of earths (and leads to them) become an issue. I have seen in the model RC field (typically ~6v) issues with what we called 'black wire corrosion' - on batteries that appeared OK the negative battery lead showed black wire corrosion , and when carefully tested showed a degraded ability to deliver current. On my car (74) I recently lost the boot light. No voltage across the supply and earth leads. Tracing back I found the lead to the boot switch broken off. The wire strands were broken off cleanly at the female spade tag on the switch. When I bared enough lead to connect a new spade connector all the strands were black. Reassembled with wires abraded and Deoxit applied. The male blade was badly discoloured. Recent work on the wiper motor showed badly discoloured male pins throughout. So, wherever I touch any wiring I check for corrosion or discoloration, clean it off, and apply some Deoxit. I also have a Porsche 928 (83), which are renowned for complicated electrics (30+ fuses , 24 relays IIRC), and on the relevant forums , whenever any problem that may have anything to do with electrics arises there are two mantras that people chant - 'Relays and earths'! Their printed circuit instrument panel has 3 earth connectors, and even then they get problems with sensors earthing innapropriately.
gEppWAR.jpg

So, check ALL the earth connections you can find - if in humid or marine climates, probably annualy is a good idea.
Just my 2c worth.
 
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