Headlight Relay Failure??

Discuss all things 1970 & later Airheads right here.
kutter
Posts: 104
Joined: Tue Dec 07, 2010 9:50 pm
Location: Central Queensland, Australia

Headlight Relay Failure??

Post by kutter »

Went to a meeting last nite on the R80.
On arrival I found that I had no rear blinkers or
stop/tail light. After the meeting rode with no
rear lights to a mates place nearby. Left the bike there
and got a lift home.Went back today, checked fuses,
bulbs and tracked back to the headlight relay.
From the diagram it is a double pole switch which I suspect
is switching power to the front lights/park/blinkers
but not the rear.
Checking the good info on relays on the internet now.
3/85 R80 Mono
5/81 R100RS - Shed Find

kutter
Rockhampton
Queensland
Australia
Garnet
Posts: 3108
Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Re: Headlight Relay Failure??

Post by Garnet »

Sounds like a bad ground. All the rear lights ground through one of the brown wires that bolt to the coil mount. Give it a good wiggle and see what happens.
Garnet

Image
kutter
Posts: 104
Joined: Tue Dec 07, 2010 9:50 pm
Location: Central Queensland, Australia

Re: Headlight Relay Failure??

Post by kutter »

Thanks Garnet,
I will check that when I go back tomorrow.
Have just checked out the relay from my
81 R100RS but it is slightly different -
has an 87a connection instead of an 87b
and no internal diodes .The diodes are
apparently in the headlight bucket on the
earlier models. The R80 is a1985 model.
Trying to find a substitute I could buy locally
if the grounding is not the answer.
3/85 R80 Mono
5/81 R100RS - Shed Find

kutter
Rockhampton
Queensland
Australia
User avatar
Airbear
Posts: 2886
Joined: Tue Aug 03, 2010 10:02 am
Location: Oz, lower right hand side, in a bit, just over the lumpy part.

Re: Headlight Relay Failure??

Post by Airbear »

Another thing to check:
It appears from the diagram that there is a connector back there for the power and ground/earth hoses to the rear lights. It'd be worth giving that a wiggle, too.
Charlie
and Brunhilde - 1974 R90/6
Image

Graduate, Wallace and Gromit School of Engineering and Design (Pending)
kutter
Posts: 104
Joined: Tue Dec 07, 2010 9:50 pm
Location: Central Queensland, Australia

Re: Headlight Relay Failure??

Post by kutter »

Thanks Airbear,
All suggestions gratefully received
and checked out.
3/85 R80 Mono
5/81 R100RS - Shed Find

kutter
Rockhampton
Queensland
Australia
ME 109
Posts: 7306
Joined: Tue Aug 03, 2010 3:00 am
Location: Albury, Australia

Re: Headlight Relay Failure??

Post by ME 109 »

Like Garnet, I'm thinking a ground.
One ground wire versus 4 individual power wires.
Lord of the Bings
User avatar
dougie
Posts: 2540
Joined: Wed Aug 04, 2010 6:19 pm
Location: Burlington Ontario, Canada

Re: Headlight Relay Failure??

Post by dougie »

Airbear wrote:Another thing to check:
It appears from the diagram that there is a connector back there for the power and ground/earth hoses to the rear lights. It'd be worth giving that a wiggle, too.
On my '87 Mono there is a 6 pin connector for the rear lights. It is a little forward of the battery, left side.
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
kutter
Posts: 104
Joined: Tue Dec 07, 2010 9:50 pm
Location: Central Queensland, Australia

Re: Headlight Relay Failure??

Post by kutter »

Absolutely correct.
It was the 6 pin/5 wires plug just under the left side
rear of the tank. Another problem solved online.
Plug was completely apart. Seems to be tight enough
when pushed completely home. Then the blinkers wouldn't
blink until 30/40 seconds after the motor was started.
3/85 R80 Mono
5/81 R100RS - Shed Find

kutter
Rockhampton
Queensland
Australia
User avatar
bbelk
Posts: 1722
Joined: Wed Aug 04, 2010 2:13 pm

Re: Headlight Relay Failure??

Post by bbelk »

The proper relay is a double pole but if you have a USA set up that does not have an on/off/park switch on the handle bar, it can work with a standard automotive single pole cause its always on and there is no need to feed the tail light through a different power source when the headlight is off.

What I did learn while I was figuring this out - was that if the relay contacts fail - it will cause the tail lights to fail too. I don't know about the turn signals.
1975 R90/6
1979 R65
kutter
Posts: 104
Joined: Tue Dec 07, 2010 9:50 pm
Location: Central Queensland, Australia

Re: Headlight Relay Failure??

Post by kutter »

Thanks for that info.
Oz gets the Euro version.
3/85 R80 Mono
5/81 R100RS - Shed Find

kutter
Rockhampton
Queensland
Australia
Post Reply