Rev conuter issues

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djsimmy
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Wed Oct 05, 2011 11:19 am

I know there are allways threads like this but,

MY rev counter has never worked since i got the car nore has the mpg...

I have taken the clocks apart and replaced the battersy with new 1's on the board etc

all the serivce light indicators etc all work fine when u turn ignition on.

every thing works fine apart from speedo is miles out(could be the wheels) and the rev counter just wont work..

its driving me absolutley mad.
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Brianmoooore
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Wed Oct 05, 2011 5:26 pm

There are always threads like this. Ones where we're expected to guess the age and model of car!!!!
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djsimmy
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Wed Oct 05, 2011 6:21 pm

sorry mate i am a retard i know..

its a 1986 tech 1 sport

things that dont work

Interior lights
Rev counter
MPG
OBC
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Brianmoooore
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Wed Oct 05, 2011 10:38 pm

All as standard, or has the engine loom and/or management been changed for later stuff?
Does the boot light work?
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djsimmy
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Thu Oct 06, 2011 7:45 am

as far as i know mate everything is standard.

dont think the boot light works either
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Brianmoooore
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Thu Oct 06, 2011 8:56 am

Sounds like fuse 27 has blown. As well as feeding the interior and boot lights, plus a few other things, it also provides an essential supply for the instrument cluster - the charging current for the SI board batteries. Without this current, the batteries may have died and need to be replaced.
Do the service LEDs work properly?
Just noticed that you've already replaced them. If you didn't charge them before fitting, it may still be the problem.
Alternatively, the signal feeds for the tacho and fuel rate on your early loom, are fed from the engine ECU to the instrument cluster via a small three pin plug and socket up above the pedal area, rather than going through the main engine loom plug and socket as on most E30s. Check that this connector is plugged together properly.
The speedo fault is probably nothing to do with the above, and is likely to be the common internal failure of the wire to the road speed sensor on the diff. Cure for this is to replace the last 300mm of wire, complete with plug.
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djsimmy
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Thu Oct 06, 2011 10:38 am

Thanks for your help and taking your time to reply will get these checked out!

the service indicator lights allways worked on ignition even on the old batterys.

none of the plastic under the dash is there so i can see the ecu and all the wiering i will have a look to see if i can find a 3 pin plugs.

i know there is a plug with nothing plugged into it but i think on the under dash panel there is something that it plugs into.
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djsimmy
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Sat Oct 08, 2011 9:49 am

these are all the 3 pin conectors i can find under the dash.. only one black one is not plugged in

i replaced the number 27 fuse and still no rev counter havnt checked the lights cos i took them all out.

Image
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ae86levin
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Sun Jan 08, 2012 3:05 pm

i bought this same problem still, can anyone help. searched the wiki pages but i cant get my head around the diagrams. the map lights dont work and there are no interior lights. dash lights do work.
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ae86levin
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Mon Jan 09, 2012 11:22 pm

bump help please
Hoobs
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Tue Jan 10, 2012 8:28 am

Have you got another binnacle you can try?

The rev counter on my track car has never worked either, although I have been told this is quite common and often because of something coming off the back of the tacho itself? Anyway, worth a look I guess.
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Brianmoooore
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Tue Jan 10, 2012 8:45 am

ae86levin wrote:i bought this same problem still, can anyone help. searched the wiki pages but i cant get my head around the diagrams. the map lights dont work and there are no interior lights. dash lights do work.
Is this the same car as above, under new ownership??
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ae86levin
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Tue Jan 10, 2012 12:31 pm

yeah same car new ownership. Am back on the scene!! trying to get a new cluster. worth a try
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ae86levin
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Tue Jan 10, 2012 11:20 pm

from the two plugs there is power to them apart from the black wire. I got a 12v tester with a light grounded it and checked for power. the other wires the light comes on is this significant. Any help will be appreciated.
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Wed Jan 11, 2012 12:21 pm

have you tried the diff wire for speedo as per brian advised ?
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ae86levin
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Wed Jan 11, 2012 1:24 pm

no as Brian mentions it has nothing to do with the revs so i havent tried as the speedo works. I;ll give it a shot any way
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Brianmoooore
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Wed Jan 11, 2012 1:55 pm

ae86levin wrote:from the two plugs there is power to them apart from the black wire.
What black wire? Where is it, and is it part of the engine loom where it comes through the bulkhead to the ECU, or is it part of the body looms?
Tacho wire is plain black!
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ae86levin
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Wed Jan 11, 2012 11:14 pm

the two plugs in the above picture one of the plugs come from the ecu i think i will double check tomorrow
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ae86levin
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Thu Jan 12, 2012 4:21 pm

Sorted now it all works. Thanks for input guys, it was the wiring that was perished :D
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