13 replies to this topic

[cagy]

Hi all,

 

Been a while since I've posted on here but again I have a car with hazards that don't want to play ball...

 

The car in question is a 94 Mayfair (Carb).

 

The indicators work fine, not an issue with them. The hazards however don't work, when you flick the switch with indicators on it cuts them off as it should do but doesn't start the indicators flashing. I've put a new relay on the indicators and the hazards and changed the switch. What could possibly be up?

 

Got MOT in a few weeks so keen to get it fixed...

 

Thanks :)

[phillrulz]

Check for voltage going to the flasher unit. ( ignore this i think its a combines flasher / hazard unit. )

 

Check for voltage going to hazard switch on light green and pink, this is the flasher supply.

 

This Wire comes from hazard / indicator flasher to the indicator relay and the hazard switch. . 

 

Sounds like you may have lost the light green / pink wire

Edited by phillrulz, 02 July 2019 - 06:34 PM.

[cagy]

I have voltage at each flasher unit... got 12v at the indicator one and about 5-6 on the hazard one on the purple and orange wire

[phillrulz]

I have voltage at each flasher unit... got 12v at the indicator one and about 5-6 on the hazard one on the purple and orange wire

 

 

Hmm thought you were ment to have a single unit...

 

 

That 5-6V is that with the hazards on ? 

[cagy]

I thought it'd be a single unit too but must be that weird crossover year...

 

No that's with them off

[cal844]

Purple and orange wire is fused at the back of the carb. Check the earths as well

[phillrulz]

I thought it'd be a single unit too but must be that weird crossover year...

 

No that's with them off

 

 

Hmm that sounds very suspisous, bulkhead fuse okay? May be corroded. 

[cal844]

I agree with Phillrulz on this, it sounds like a corroded or broken connection

Also on my 1994 car there is a relay under the dash(indicators) and the yellow one at the wiper motor(hazards)


Also look behind the switch connections for corrosion or burnt insulation.

Id also recommend fitting blade fuse holders, or at least longer inline fuses to the 4 inline fuses behind the speedo binnacle, I've had issues with lights due to corrosion in this area

Yes I'm potentially giving the OP slightly unrelated tasks but Its worth it for extra reliability

Edited by cal844, 02 July 2019 - 08:43 PM.

[72r1mini]

Just went through this, mine ended up being a fuse to short for the purple orange wire. One way to confirm is to see if your dome light works. They have the same power source (fuse)

[matt615]

As others have said, if you only have 6v at the hazard flasher then you probably have a dirty connection somewhere.

Start with the hazard fuse, check and clean up the connections and go from there.

[Ethel]

6v is probably normal.

Indicator flasher contacts are closed at rest, so they failsafe and light even if they don't flash.

Hazard flasher contacts are the reverse (normally open contacts) so they don't run the battery totally flat, unlike indicators they can be used without the key in & ignition on.

For hazards to work this way, and still flash if smashing half your lights in a bump is the reason you're using them, they have an internal heating coil to bend the bimetallic strip and close the contacts, that adds resistance when the hazards are off.

[cooperd70]

I had this very recently. It'll be a dirty connection on the inline bulkhead fuse. Popped the fuse out, cleaned the connections in the fuse holder and each end of the fuse and Bob's your uncle.

[phillrulz]

6v is probably normal.

Indicator flasher contacts are closed at rest, so they failsafe and light even if they don't flash.

Hazard flasher contacts are the reverse (normally open contacts) so they don't run the battery totally flat, unlike indicators they can be used without the key in & ignition on.

For hazards to work this way, and still flash if smashing half your lights in a bump is the reason you're using them, they have an internal heating coil to bend the bimetallic strip and close the contacts, that adds resistance when the hazards are off.

 

Surely i cant be normal. For there to be 6v there need to be current flow. Since the hazard switch / relay is off there should be full battery voltage as no path to ground. unless there is such high resistance prior to flasher that the impedance of the multimeter measuring the voltage makes a voltage divider. 

[Ethel]

No details on how the voltage was measured. 6v voltage drop across the internal resistance of the flasher sounds plausible.