Indicators on the blink

[JohnG]

All

 

Returned home, just before Christmas, to find that the reason I was getting some strange looks out on the road, was because the indicators were not performing to specification.

 

Problem;

N/S indicators working

O/S indicators not working

 

Actions to date;

- checked the earth (to body) strap in the boot (N/S)

- replaced the flasher unit with a Lucas replacement

- visually checked as much of the wiring as I can get to

- checked each bulb and renewed the front O/S main bulb, which seemed 'flakey'

 

Result;

N/S indicators working

O/S rear bulb working

O/S front bulbs (main and repeater) not working.

 

I had to have the ignition on to run the indicators

This meant that the fuel pump was running

 

I noticed that, when the indicators work, the fuel pump slows

Is this Right?

 

I started the car and operated;

- the N/S indicators; all OK

- the O/S indicators rear bulb working front bulbs not working

and the engine stopped!

(Fuse blown)

- fuse replaced

 

I am now at the point where I have no O/S front indicators and am beginning to run out of idea's, can you help Please?

 

Any and all suggestions gratefully received

[Steves_TR6]

Sounds like a short on the os front indicators?

[RobH]

Odd that a fuse blew and stopped the engine as the diagram shows ignition on a different circuit from the indicators - which fuse was it (what colour are the wires to it? ). Did the fuse blow co-incident with you switching something on ?

 

It doesn't sound like a short circuit in part of the indicators to me as that would stop all the indicators from working.

 

Since you say both the main bulb and the repeater at the front OS are both not working, that would point to a poor common connection in the feed to them or perhaps to the earth connection if that is common to both. Look for an in-line connector in the feed line - possibly a bullet type -as that may be bad.

[Prefect]

if you want to test it without either boiling the coil or running the fuel pump then:

Pull the inertia switch to isolate the fuel pump and pull off a lead to the coil.

 

The pump and the ignition are not fused. (If wiring correct).

TR Fuses only blow for a short to earth, they are like nails!

I dont agree that all indicaters would not work if there is a short to earth.

Only the side that is switched (selected) is in circuit at any time unless you have hazard warning lamps.

Check the exit from the loom down by the front offside corner under just under the headlight.

[RobH]

"I dont agree that all indicaters would not work if there is a short to earth.
Only the side that is switched (selected) is in circuit at any time unless you have hazard warning lamps."

 

Yes but the rear one was working - hence likely there is no short. Flasher units do not like running into short circuits and front and rear are in parallel on the same terminal.......

Edited January 2, 2017 by RobH

[Prefect]

Hi RobH

Your logic is sound.

But it may be that a high restance short at the front of the car stopped the front indicators working but left the rear functioning.

This may have developed into a hard to earth short which blew the fuse after the wires / connectors were moved during investigations???

[HarveyCoppock]

As prefect said, probably something nasty happening to wiring under the headlights, there is enough of it around there. Maybe take out your radiator ducting and air filter?, offside front indicators will be green wires with white trace? Maybe disconnect the indicators at the bullet connectors there and see if it still blows a fuse (unless you have a multimeter), then you would know if it was wiring up to that point, or wiring around the fittings or the fittings. Perhaps the sleeve has pulled off a bullet connector? Or insulation worn through on a metal cable clip?

[JohnG]

Gents

Thanks for all, the thoughts

 

Yes . . . I tend towards the problem being at the O/S front area

Yes . . . The connectors are the old BL bullet type favourite

Yes .. . . The fuse confused me a bit, but, it appears from the circuit diagram that the coil LT feed is fused. Or am I reading it back handed?

 

I fitted a new fuse box (blade type fuses) in the summer and all has been hunky dory since, until this incident.

 

I "down rated" the fuses, having read that modern fuses are rated differently to the old glass ones

 

The fuse that blew was rated at 15 amps

 

Had our granddaughter all day today, so, plan to start on the problem again tomorrow.

 

1st job, check the bullet connectors

Disconnect, clean and reassemble. Protect with Vasaline?

 

Then look for potential problems with earth's and wiring.

(I plan to realign the bonnet, so the rad cowl was coming out anyway)

 

Yes, I have a multimeter (not sure I fully understand how to use it but hey . . . We can but try.

 

Clean everything I can get my hands one.

 

Liberal use of Vasaline?

Edited January 3, 2017 by wjgco

[Cew]

I had a similar anomaly with my rear N/S, turned out to be the bulb holder not making good enough contact with the lamp. I seem to remember having to solder it somehow. Not sure if the same would apply to the fronts though.

[JohnG]

I had a similar anomaly with my rear N/S, turned out to be the bulb holder not making good enough contact with the lamp. I seem to remember having to solder it somehow. Not sure if the same would apply to the fronts though.

Well worth noting though Clive.

 

The holders seem to be so simple, that they should not offer problems.

Famous last Words!

[Steves_TR6]

The rear lamp holders do suffer earth problems, and the new replacements dont seem to be very good.

 

I repaired my old holders after failing to get the new replacements to work reliably.

 

Usually seems to be the earth connection that is unreliable.

 

Ive not touched the front lamps so cant comment on those, but the above comments are all valid.

 

Check all the connections, check for shorts, also check that the wiring ( especially to the fuse box) is as it should be as if the main (ignition?0 fuse blew because of an indicator fault thats not right.

 

Good luck!

 

Steve

[Guest ntc]

It will be the side repeater earth or other and then the flasher unit.

[JohnG]

Got it sorted, finally.

 

Replaced the earth cable to the O/S front indicator/ side light assembly.

 

The assembly looks to be in good order, but, rereading the posts above, I'm thinking that i may be staring down the barrel of replacement.

The lens is in good order

The rubber boot could be better

The problem seems to be getting the bulb holder assembly. Can't identify anyone selling this part, but the whole assembly is available (repro's I assume), at prices up to £150.00 each.

 

Does anyone know of a decent source, I plan to ring Collectors Car Parts in Egham, to see what they have.

 

At the moment things are working.

I am loathe to muck things about, but, at the same time, want the electrics as reliable as they can get.

Edited January 19, 2017 by wjgco