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Re: Wiring up heated wing mirrors?
Posted: 29 Nov 2011, 07:26
by ewenmaclean
Hi Cruz,
for illuminated switches, you need +12v, earth and load (to relay in your case), since the internal light is wired up in parallel not in series. I am guessing it is
pin 1: to relay
pin 2: ignition feed
pin 3: earth (probably the gold one)
the pin to the relay maybe marked "acc" which would help.
That's just a guess mind.... I'd get a multimeter out and check where there's no resistance between pins (+12v and acc when on), and infinite resistance (earth and +12v when on) - that'll tell you for sure.
Ewen
Re: Wiring up heated wing mirrors?
Posted: 29 Nov 2011, 09:50
by Cruz
I've checked the resistance using the lowest 200 setting on the digital meter
When off the meter doesn't even register any reading between any pin in any sequence
When on the two silver pins 1 & 2 show zero resistance
When pin 1 or 2 is connected to the gold pin 3 the resistance is about 50
Re: Wiring up heated wing mirrors?
Posted: 29 Nov 2011, 10:03
by ewenmaclean
Hi Cruz,
I hope when it's off you have infinite resistance between all pins!
From what you say what I previously said is right then - the gold pin 3 is to go to earth (to earth the internal illumination bulb), pin 2 is +12v, and pin 1 is to the relay.
Ewen
Re: Wiring up heated wing mirrors?
Posted: 29 Nov 2011, 10:10
by Cruz
ewenmaclean wrote:
That's just a guess mind.... I'd get a multimeter out and check where there's no resistance between pins (+12v and acc when on), and infinite resistance (earth and +12v when on) - that'll tell you for sure.
Ewen
Thanks for all your help Ewen. I take it the bit above in bold should be off and not on?
I get exactly what you have written if that is the case
Infinite between all pins when off and zero between the relay and 12v+ when on
I'll get my coat and get cracking

Re: Wiring up heated wing mirrors?
Posted: 29 Nov 2011, 10:16
by ewenmaclean
Hi Cruz,
oops - that's a pretty crucial typing error - sorry about that. Thankfully I don't write instructions for diffusing bombs.
Indeed I did mean infinite resistance when off! When I first read your post I thought it said you had no resistance when off, but reading again it seems it's all good.
Good luck fitting it all together!
Ewen
Re: Wiring up heated wing mirrors?
Posted: 29 Nov 2011, 11:16
by Cruz
Updated wiring diagram
BLOODY RAIN!!!!!
Re: Wiring up heated wing mirrors?
Posted: 30 Nov 2011, 08:17
by Cruz
The rain seriously hampered my progress and the only place I could see to mount the relay was under the dash between the steering column and the drivers door (my early fusebox relay section is full due to the headlamp relays). There's not really anywhere else around the fusebox due to the glovebox.
Re: Wiring up heated wing mirrors?
Posted: 30 Nov 2011, 08:49
by jaybeeonline
Could you not piggy back on the switch wire from the heated rear window switch assembly, wire through the relay as per the sketch to feed the mirrors?
Would save having an additional switch for the same function.
J.
Re: Wiring up heated wing mirrors?
Posted: 30 Nov 2011, 09:04
by Cruz
jaybeeonline wrote:Could you not piggy back on the switch wire from the heated rear window switch assembly
What's that?
Re: Wiring up heated wing mirrors?
Posted: 30 Nov 2011, 09:23
by jaybeeonline
Re: Wiring up heated wing mirrors?
Posted: 07 Dec 2011, 08:38
by Cruz
After quite a number of shower/hail interruptions I finally finished wiring the mirrors.
My van is early with ceramic fuses so the small relay box is already full with my headlight relays so I had to position the relay on the chassis between the steering column and the drivers door.
Here's a rough wiring diagram (crap work paint program). I used the coloured wire shown in the diagram as well as non-insulated crimped connectors including piggy back connectors where I wanted to connect two wires. (all from vehicle wiring products online)
It wasn't a hard job even for a relative novice

Re: Wiring up heated wing mirrors?
Posted: 22 Jun 2012, 07:47
by ninja.turtle007
What size wire have you used between the relay and the mirror?