What have I done wrong?

Various, various and more various!
Post Reply
User avatar
filthyjohn
*** V3M DONOR ***
Posts: 2693
Joined: 12 Sep 2006 09:07 pm
Location: Sunderland, Ringpiece Of England

What have I done wrong?

Post by filthyjohn » 21 Dec 2008 02:05 am

OK chaps,
My brother's been fitting a CD player to the ex-vario, to get some reasonable sound quality there are some rear speakers involved. However, now I've lost the fuel gauge, rev counter, ambient temp gauge and coolant temp gauge.
The radio/CD works fine and all 4 speakers are ok too. All fuses are fine but the wiring's very confusing and haynes is zero help. The dash illumination fuse (no.5) blew twice but has been fine since.
Anyone know what links all the knacked items? Clearly either power to the gauges, or common earth.

Help me I'm stumped!

:cry:
'87 Nissan Sunny
'95 945 LPT
'90 340 3dr
'87 360 GLT
'87 765 TIC
'75 Manta A
'70 Rover P5 V8
'67 MGB GT
'62 amazon 2dr

whiskeyonesix
Posts: 373
Joined: 24 Nov 2008 12:43 pm
Location: Perth Australia
Contact:

Post by whiskeyonesix » 21 Dec 2008 03:21 am

I had much the same problem a few years back when I tried to use the existing wiring to wire up an aftermarket CD player to my 740 (Why I just didn't use a wiring loom adaptor still escapes me)

Turns out it wasn't earthing properly causing those little problems. I ended up running a separate earth/live off the ignition and putting in-line fuses in. It was a terrible hash-up as I recall, but got the job done!
MKIII 360GLT Aus-spec B200EA 239K
Mods: custom paint fade
New Cylinder head.
Auxilary cooling fan.
195/60/14 Pyonghung Ditchfinder tyres
Vario Vents FTW

G8 4 DRFTN etc....

User avatar
filthyjohn
*** V3M DONOR ***
Posts: 2693
Joined: 12 Sep 2006 09:07 pm
Location: Sunderland, Ringpiece Of England

Post by filthyjohn » 21 Dec 2008 07:26 am

I fear I may haveto do the same here.
Forgot to add last night, a multimeter confirms there's a resistance value for the fuel sender, and the correct rpm signal too. So the problem seems to lie with the instruments' power or earth supply, but not on the gauge cluster itself.
sm14
'87 Nissan Sunny
'95 945 LPT
'90 340 3dr
'87 360 GLT
'87 765 TIC
'75 Manta A
'70 Rover P5 V8
'67 MGB GT
'62 amazon 2dr

kaos
Posts: 1298
Joined: 09 Jul 2007 10:34 pm
Location: Somerset

Post by kaos » 21 Dec 2008 01:24 pm

you havent managed to pull a cable out from behind the dash have you?
Image

Vart
Posts: 363
Joined: 04 Jun 2005 05:11 pm
Location: Suffolk

Post by Vart » 21 Dec 2008 01:29 pm

mines done this - there is a red (on mine anyway) wire that splits feeding power to the radio and the dash. i'd cut it for some reason and then resoldered it badly and the dash lighting, tacho, fuel / temp gauges failed when going over bumps and the like.

the multiplugs had a thick red going in then a thinner one coming back out the same socket and off up into the gubbins behind the dials. see if this has been cut as it appears to be pointless at a glance.

hope this helps

toby
1986 1.4DL - 147,000 - C746 VRT

User avatar
volvodspec
Posts: 1921
Joined: 06 Dec 2008 09:35 pm
Location: Netherlands.
Contact:

Post by volvodspec » 21 Dec 2008 05:39 pm

electrics failing after installing a radio in a 300 series car is a well known problem:D with an easy fix,

for some stupid reason volvo desided to split 3 wires and put a connector on these wires. when one of the 3 or more wires are disconnected from eachother, the rest of the dash won't get the electrical current.

so, behind your radio.reconnect the 2 green, 2 brown and 2 red/black wires to eachother, and then connect the radio to these wires and problems are solved and you have a working radio!

germ
*** V3M DONOR ***
Posts: 1222
Joined: 15 Nov 2006 08:14 pm
Location: Hitchin Herts England - South Of France - NI Ards

Post by germ » 21 Dec 2008 09:13 pm

Yup exactly whats Volvodspec said. :)
Volvo 340 Image 1988

User avatar
filthyjohn
*** V3M DONOR ***
Posts: 2693
Joined: 12 Sep 2006 09:07 pm
Location: Sunderland, Ringpiece Of England

Post by filthyjohn » 21 Dec 2008 11:27 pm

Cheers lads, I shall give that a try tomorrow and report back. I do remember being puzzled by the mulitple redundant wires arranged in pairs. I drove all the way to Pete Farrell's and back today with no fuel gauge!
sm43
'87 Nissan Sunny
'95 945 LPT
'90 340 3dr
'87 360 GLT
'87 765 TIC
'75 Manta A
'70 Rover P5 V8
'67 MGB GT
'62 amazon 2dr

pettaw
*** V3M DONOR ***
Posts: 1673
Joined: 15 Aug 2004 07:39 pm
Location: London, UK

Post by pettaw » 21 Dec 2008 11:51 pm

Teah, you've lost a switched live connection somewhere. That's the red/black striped wire. As the other's say it connects through the radio terminals on the later cars. The reason only half the dash doesn't work is because the other half gets its live through another wire. You'll be able to get some warning lights like the rear window heater and rear fogs, but the main ignition warning lights etc along with all the gauges won't be working.

User avatar
volvodspec
Posts: 1921
Joined: 06 Dec 2008 09:35 pm
Location: Netherlands.
Contact:

Post by volvodspec » 22 Dec 2008 05:30 pm

pettaw wrote:Teah, you've lost a switched live connection somewhere. That's the red/black striped wire. As the other's say it connects through the radio terminals on the later cars. The reason only half the dash doesn't work is because the other half gets its live through another wire. You'll be able to get some warning lights like the rear window heater and rear fogs, but the main ignition warning lights etc along with all the gauges won't be working.
the red-black wire is a feed switched by ignition, green is a direct battery feed, and brown is the ground. even if 1 of the ground wires is loose, half the dash won't work, or you'll get all kind of crazy things.

Post Reply