Morris Minor Owners Club

Recently bought a 63 saloon with loads of little bits to do.
The indicator stalk was broken and the car had white front lenses. The old flasher unit was swinging in the breeze.
I have put the new stalk and l front light units on.
I also screwed the flasher unit to the bodywork.
Now I get a clunk from the relay box but no indicators at all.
The rear indicators have already been wired to the front loom bypassing the relay.
When I put the green and green/brown together the lamps will light up.
Is it the relay or flasher unit please?

I am not sure what it is your refer to as "the relay". Minor didn't have any relays fitted at the factory. Does your car have some kind of modification by a previous owner?
Jim

The workshop manual refers to it as a relay. The silver box bolted to the inner wing.

Do you have a wiring diagram for your car? The circuit is quite straightforward:

Green is the power supply from the fusebox to the flasher
Green and brown takes the power from the flasher to the indicator switch
Light green goes from the flasher to the warning light on the indicator arm
The Indicator switch should connect the green and brown to green and white (for right hand indicator) or green and red (for left)

If these connections are correct then I suspect you may have a faulty flasher.

Good luck
Jim

If you mean the (usually) cylindrical box with three connections this is the flasher unit. Note that the correct connections for this are: green on the left, light green in the centre and green and brown on the right.

If connecting green and green and brown causes indicators to light then that would suggest that you have connected the switch correctly and the flasher is not working.

Jim

The indicator wiring IS generally very simple but is slightly more complicated on Minors built around that time where the brake lights also act as flashing indicators. In order to do this Lucas built a box of tricks generally referred to as a DB10 indicator relay which has 8 wires going to/coming from it.
That is what the OP is talking about. It sounds as if he is trying to modify the wiring to his lights but has perhaps not fully explained this?

It does have the 8 wire box that the workshop manual refers to as a relay. I haven’t modified it, I suspect the previous owner has. It also has a 3 wire flasher unit.
However, the workshop manual does have exactly this configuration on one of the wiring diagrams.
Thanks for the help though, it confirms my suspicions that the flasher unit may be done for

Jim McCrae wrote: ↑Mon Jun 24, 2024 6:49 pm Minor didn't have any relays fitted at the factory.
Jim

JIm
What the OP has is a DB10 Relay system, which flashed Red Indicators to the rear (using Brake Lights) while the front 'marker' light contained a 5/21W lamp to provide a front White Indicator in addition to side light..

This was factory fitted 61-63 (earlier commencement for USA) between Trafficators demise and the final post '63 Indicators.

Often these systems have been Bar-Stewardised to separate Amber Indicators, leaving the DB10 in circuit as simply an over complicated Indicator system.

This problem will be impossible to diagnose from the description provided as we only have part of the story.

My own car, although a SII, was modified in the 1990s to have the DB10 Loom , which a subsequent owner then partially bypassed.
I've partially restored it to it's intended operation.

LorliC wrote: ↑Mon Jun 24, 2024 7:07 pm

LorliC
What 'Indicators' have you got on the exterior of the car? Do you now have separate Amber aftermarket lamps front & rear?
If you can provide photos of the Relay Unit, Flasher Unit and Brake Light Switch (showing the wiring colours), I can perhaps establish to what extent your system has been altered.

That’s excellent news, I really didn’t understand the purpose of the relay box so I will wire it as a simple 3 pin flasher unit system.
I have changed the front lights using the later amber/clear to avoid confusing other drivers. The rear has been done prior to my ownership.
I will post a picture of the current wiring before I alter it, just to clarify my questions.
Thanks for the advice.

Here's a brief explanation as to how it works.

LH Diagram - steady Brake Lights supply straight through to rear lamps Terminal 5 to 3 & 7. Simples.

RH Diagram - LH Indicators operate, power to terminal 4 pulls Relay lower connection on diagram to connect 1, 2 & 3. Flasher now flashes Front Lamp and Rear Brake Lamp.
Stay with RH diagram, if you now brake, the steady Brake supply can only go to 5 to 7, and NOT to 3.
Terminal 3 still has the Indicator supply pulsing to it from the Flasher Unit
So you get a steady Brake Light on the RH Lamp and a Pulsing Brake Light for the indicator on the LH side.

Obviously a Mirror image on the RH side of the Relay if indicating Right.
Simple but ingenious; served the entire US Motor industry for many decades with their Red Brake Light system.