Flasher unit relays

[Stephen Aitken]

Sourced some led bulbs and hooked them up. I must say what a difference to the headlights and indicators. I also replaced out all the gauge bulbs and I now can see what speed I’m doing at night!!
However one slight niggle is that the led bulbs needs separate flasher unit also for hazard lights but don’t have the reassuring click..it’s really annoying me not hearing it. I know you can get a clicking sound relays but I’m at a loss to know how to plug it in. It has 3 pins but don’t know what goes in the third pin (the original relays just have the two pins so is an easy hook up). Does it need an earth connection and if so how do you do that ??
Thanks
S

[Peter Cresswell]

Hi Stephen,
You could get one from these people, and ask for the wiring diagram!
https://www.autobulbsdirect.co.uk/led-flasher-unit.html

You should also be aware that under the new stricter MOT test you risk your car failing with LED headlights, fitted into a 'traditional' headlight unit. This is part of the alignment test and 'traditional' H4 headlight bulbs have a single light source at the focal point of the parabolic reflector whereas the LED bulbs have multiple light sources and so cause the beam to scatter. This occurs with HID bulb fitments in 'traditional' headlight units as well. It is also at risk of a fail for not having self levelling suspension. Additionally all bulbs must be E marked now.
Personally, I have found that making sure the wiring and connectors are in good condition improves the standard H4 headlights enormously, and better headlight units give a further improvement. I use Lucas H4 units, but better (and more expensive) are Cibie H180 units, which I have used in the past on road rally cars. When fitted with the high light output bulbs from Phillips or Osram give an added improvement and the bulbs draw the normal 60/55w of power and are E marked.

[Stephen Aitken]

Ok thanks. My B is coming up for an mot in the next couple of weeks so I assume safer to replace the less for that? Must admit not heard of this being a fail

[Vic Butler]

It's headlight LED bulbs that fail because of light scatter. My Land Rover has had LED side and indicator bulbs with clear lenses for over 10 years and no problems.
You need an electronic flasher relay for LED bulbs.
. Vic Butler

[Peter Cresswell]

The actual failure comes under Section 4.1.4 Compliance with regulations 'c Light source and lamp not compatible'. It is a 'Major' Fail.

See here for all the MOT requirements for 'Private passenger and light commercial vehicles' https://www.mot-testing.service.gov.uk/ ... class3457/

Some testers might interpret this to encompass side lights and indicators also, as the new rules have given them leeway to interpret the regulations, rather than as previously they had black and white circumstances e.g. the light is either working (a Pass) or is not working (a Fail).