Live speedo!

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Steve
Posts: 374
Joined: Sat Nov 24, 2007 22:42
Location: Bolton Lancashire

Live speedo!

Post by Steve »

My indicators and hazards ceased to work (Was going to say on the blink, but they didn't :lol: ) Fitted a new hazard switch (it was faulty on the rocker contacts) and a new flasher unit (cheap nasty thing had shorted out inside) so while I have the dash apart, I have installed a temp gauge and oil pressure guage (both Smiths) I had an amp meter and a nasty oil pressure guage that squirt oil over the back of the speedo pod. The panel lights were not very bright so out with the meter which showed only 3-4 volts, after a bit of head scratching I put a new earth on to the body instead of the speedo housing, nice and bright panel lights ... but the earth still puzzled me, meter out again and the speedo housing is showing 9 volts when ever a switch is operated which means that on the panel lights, I had a 12v supply and 3-4v going through the earth on the lamp and back to earth via the speedo to the body hence dim panel lights.

Anyone have an idea why I am getting 9volts on the speedo and where is it coming from?
Steve

Things go better with a Moke
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grantourer
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Location: Kenilworth. UK

Re: Live speedo!

Post by grantourer »

Hi. There should be an earth point next to the regulator, which is at the top of the speedo, is it connected? and is the nut and shakeproof still there. Should this be missing you will get random faults.
Regards, Graham & Judith
1981 Aussie Moke
1989 Portuguese Moke
1979 Clubman Estate
User avatar
Steve
Posts: 374
Joined: Sat Nov 24, 2007 22:42
Location: Bolton Lancashire

Re: Live speedo!

Post by Steve »

Yes, the earth point is there but even when the earth is disconected, I still get 9v on the housing which also means that the 9v is going to the body. All the switches/lamps etc are terminated correctly with 2 spade connectors on each side of the regulator.
Steve

Things go better with a Moke
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grantourer
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Location: Kenilworth. UK

Re: Live speedo!

Post by grantourer »

Hi Steve. probably the best thing to do is disconnect the power cable, not the earth from the battery. Put one side of your continuity meter on the earth post of the battery, and check you have good earth's to the battery.You should measure very low resistance's. Any bad earth connections act like resistors. A bit tedious, I know. I had a similar problem on an old Land Rover 86", turned out to be an earth connection between body and chassis.
Regards, Graham & Judith
1981 Aussie Moke
1989 Portuguese Moke
1979 Clubman Estate
User avatar
Steve
Posts: 374
Joined: Sat Nov 24, 2007 22:42
Location: Bolton Lancashire

Re: Live speedo!

Post by Steve »

Thanks Graham that will be todays mission.
Steve

Things go better with a Moke
User avatar
Steve
Posts: 374
Joined: Sat Nov 24, 2007 22:42
Location: Bolton Lancashire

Re: Live speedo!

Post by Steve »

Earths checked out OK so back to head scratching :roll:
Steve

Things go better with a Moke
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grantourer
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Posts: 1126
Joined: Fri Dec 31, 2010 15:55
Location: Kenilworth. UK

Re: Live speedo!

Post by grantourer »

Hi Steve. What was the reading between the speedo earth and the battery negative connection, in Ohms?
Regards, Graham & Judith
1981 Aussie Moke
1989 Portuguese Moke
1979 Clubman Estate
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