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M

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Discussion Starter #1
Replaced the sender unit in the diff and the speedo still isn't working :(
The voltages all seem correct right up to the speedo, until I connect the sender unit :confused:
Then the earth and 2 live wires seem to swap polarity when the engine is running.

What do I do now ???????
 

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Try checking the drive in the gearbox for the sender :confused:

Make sure your getting the signal up to the speedo head itself some cars have a resistor thingy on the back of the speedo head that can fail and stop the speedo working :confused:
 
M

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Discussion Starter #3
thanks speedy I'll check for a resistor. Mind you, the console from the Silverstone did exactly the same when I put it in the V6 as a trial. Everything worked except the speedo.
Been thinking about this again. I'm gonna check the earth. I have a funny feeling I did find something strange, but didn't pay attention at the time.
Will test and reroute the earth tonight and see what happens.
 
M

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Discussion Starter #4
OK done some more testing.......

The +ve to the speedo gives 12v when the ignition is on, but the engine isn't running.
The signal wire to the speedo gives no voltage when in this same state.
The tests at the plug where the sensor joins to to the wiring loom also give the correct results.

When the engine is running, the +ve gives 0v and the signal wire gives 12v, even when the car is standing still :confused:

There isn't any tests for voltages when the engine is running in the manual. But somehow I think I have a wiring or ECU fault :eek:

The injector light gives the code: 1-2-5-1 - control unit EPROM :eek: :eek:

OH NO...AAAAAAAAAAAAARGH !!!!!!! :(
 

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But is the drive in the gearbox ok??????

Alfapat had a similar problem and it was the drive at fault..............do a bit of searching :D
 
M

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Discussion Starter #6
Dunno how to check the drive. I can't see it so would have to remove the plenum and other stuff to get proper access :(
Unless you have a tip ;)
 
J

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Discussion Starter #9
take the sender out of the gearbox and connect a drill to the square drive bit and then see if the speedo works. if it does you know its the gearbox drive.
 
M

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Discussion Starter #10
thanks JB, I knew if I held off long enough you'd come to the rescue ;)
I will rewire the speedo circuit if it isn't the gearbox drive. I have a funny feeling that the sensor isn't getting a voltage when the engine is running. The sensor gets it power from pin 1 on plug A of the instrument cluster. This goes dead when the engine is running, but is OK when just the ignition is on. I think I'll do temp rewire before the drill test as with no voltage, the sensor wouldn't work anyway............hmmmmmmm.........a chance to tinker again !!!!!
 
M

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Discussion Starter #12
Instead of soldering, I'll let you weld the connections :p

It's a pain not knowing how fast you're going, esp on the motorway.

What speeds were we doing the other day ????
 
J

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Discussion Starter #13
m/way? topped about 100ish and cruised at 90 nothin crazy
back roads? about the same :D :D
 
M

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Discussion Starter #14
Hmmm........nice.

The V6 definately has more pull at high speeds than the Silverstone :)
 
J

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Discussion Starter #15
gotta do run again soon :D i'll take down by me old house at c/hill some cool roads
 
J

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Discussion Starter #17
vrrrom vrrrom bwrrrrraaaaaaaaaarrrrrrrrrrr vroooom vrooooooom bbbbbbbwwwwwwwwrrrrrrrrrraaaaaaaaaaaaarrrrrrrr wooosh!!!!
 
B

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Discussion Starter #18
jason77 said:
vrrrom vrrrom bwrrrrraaaaaaaaaarrrrrrrrrrr vroooom vrooooooom bbbbbbbwwwwwwwwrrrrrrrrrraaaaaaaaaaaaarrrrrrrr wooosh!!!!
You guys just crack me up.... :cheese: :cheese:
 
J

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Discussion Starter #19
you shold hear me actually make the noise.. i'm dead good at it :D
 
M

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Discussion Starter #20
As Jase pointed out to me.......the reg on my V6 is N*** BWR.........The BWR is the noise the engine makes............bbbbbbbwwwwwwwwrrrrrrrrrraaaaaaaaaaaaarrrrrrrr !!!!!!
 
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