Classic cars forum & vehicle restoration.

[SplodgesDad]

Hi all, can anyone help please?
I recently had my V8 Pilot upgraded to 12v throughout but now the indicators that I had fitted when she was running a split 6/12v system no longer work.

I upgraded the flasher unti from 6v to 12v, as well as replacing all the bulbs, so I'm confident the voltage itself is not the problem. (Both flasher units came from a motorbike shop as my local motor factors only stock modern stuff)

Because the car is positive earth I double checked the wiring as it has had a few modifications over the years and have now removed the previous connections to the flasher (bimetallic type) unit as they weren't wired as a diagram I saw recently.

I can't find if wiring the 3 pin connector incorrectly will screw the unit up so bought a new 21w x 2.5w car unit (BL type), in case the 12v car battery was too much, and connected that (iaw the diagram, X to live, L to negative, and P to the dash light) but still can't get anything to work.

I've taken the flasher out of the cct and tested the bulbs (2 x 10w each side), dash light and switch and all lights up as expected (not flashing). I'm now stumped, has anyone got any ideas where I'm going wrong?

[Phil - Nottingham]

L = Lamps
P = Panel; warning light
X = Live (+ve or -ve)
_________________
Rover P2
Rover P4
Rover P5 & P5B
Land Rover S2 & S3
Morris Mini Traveller Mk2

[SplodgesDad]

Thanks Phil, I take it from your post that it doesn't matter which way round the X and L go if earth is either positive or negative?
Not what was stated on the diagram I saw but hey ho, live and learn!

[Phil - Nottingham]

If it is an old type mechanical/thermal then they are not polarity conscious but quite sensitive to bulb loading which has to be as stated to get the correct 60-120 flashes per minute (engine running)

The P terminal can have different earthing via the lamp however either via direct earth on a single bulb holder or via the flasher switch where 2 INSULATED holders are used ie one for left and one for right
_________________
Rover P2
Rover P4
Rover P5 & P5B
Land Rover S2 & S3
Morris Mini Traveller Mk2

[SplodgesDad]

Thanks again Phil, I'm using the bimetallic strip flasher unit, each bulb holder is earthed individually, and I've wired the connections straight across the battery in case there are any iffy connections under the dash.

I wired the flasher again as you suggested and tried again.

The battery is fully charged and I've tested with the engine off and running but still no joy.

I have my doubts about the alternator (the dynamo was removed prior to my ownership) that was fitted previously as the battery keeps discharging, could this be drawing current so that the flasher unit isn't getting sufficient oomph to heat the strip correctly? (Just tested the alternator and it's only pushing out 12.5v when the engine is running)

[SplodgesDad]

Update time, it turns out that because I was using aftermarket motorbike indicators with 10w bulbs, there wasn't enough current draw to activate the car flasher unit. Fitting 21w bulbs will fix this apparently.

As it was, I went back to where I got the bike flasher unit from and got the unit replaced which cured the snag, looks like it was duff straight out of the box!

[Phil - Nottingham]

I did say the bulb rating is critical on these and 12.5v is not sufficient to keep the battery adequately charged either

21w is really safer for car indicators
_________________
Rover P2
Rover P4
Rover P5 & P5B
Land Rover S2 & S3
Morris Mini Traveller Mk2

[SplodgesDad]

I've been talking to an ex auto electrician about the alternator and it looks very much like the original alternator conversion was a hatchet job and never worked properly anyway.

Looks like I'll be forking out again to get it done properly!

[SplodgesDad]

I've been talking to an ex auto electrician about the alternator and it looks very much like the original alternator conversion was a hatchet job and never worked properly anyway.

Looks like I'll be forking out again to get it done properly!

[Phil - Nottingham]

It does seem a good idea - some older alternators need an extra sensing wire to charge
_________________
Rover P2
Rover P4
Rover P5 & P5B
Land Rover S2 & S3
Morris Mini Traveller Mk2