I want my tach & I want it now!
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Help? One week til Gateway Carrera Classic (DE) and I still haven't gotten my tach to work. I looked briefly at the instrument schematic and it seems like the tach is triggered by the hall sensor on the flywheel? It's gone. On the DME pinout diagram pin #21 is labeled:
Conn. point 4-pin terminal. 2 (tachometer - 1)
I found a Matchbox car sized brown Bakelite connector on a little metal bracket that has six round pin receptecles with only 4 pins in it, but the wire colors don't match the wires on the schematic. All I want is the wire from the DME to the tach, but I threw away the old DME connector.
Help! <img src="graemlins/c.gif" border="0" alt="[ouch]" />
Conn. point 4-pin terminal. 2 (tachometer - 1)
I found a Matchbox car sized brown Bakelite connector on a little metal bracket that has six round pin receptecles with only 4 pins in it, but the wire colors don't match the wires on the schematic. All I want is the wire from the DME to the tach, but I threw away the old DME connector.
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Help! <img src="graemlins/c.gif" border="0" alt="[ouch]" />
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Hey Russ,
It looks like it should be a grn-blk wire coming from connector b-3 on the back of the instrument panel. Sorry, I have no idea where the 4 pin connector is. Further checking, It is also suppose to be a grn-blk wire at the dme. So, if there is more than one at the dme, you can always use an ohm meter and figure out which one. Hope That helps.
Later,
Rob <img src="graemlins/wave.gif" border="0" alt="[byebye]" />
It looks like it should be a grn-blk wire coming from connector b-3 on the back of the instrument panel. Sorry, I have no idea where the 4 pin connector is. Further checking, It is also suppose to be a grn-blk wire at the dme. So, if there is more than one at the dme, you can always use an ohm meter and figure out which one. Hope That helps.
Later,
Rob <img src="graemlins/wave.gif" border="0" alt="[byebye]" />
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Rob,
Thanks a bundle man. I traced the wire back to a SIX pin connector with 1-4 together and two more spaced over. The wire colors are correct. The "tach" wire a constant 8v current
with the key switched on. Is this correct(pardon my ignorance)? How does the tach work? I was going to connect this wire to the tach output on the MSD or the trigger wire from the SDS.
Thanks a bundle man. I traced the wire back to a SIX pin connector with 1-4 together and two more spaced over. The wire colors are correct. The "tach" wire a constant 8v current
with the key switched on. Is this correct(pardon my ignorance)? How does the tach work? I was going to connect this wire to the tach output on the MSD or the trigger wire from the SDS.
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[quote] "tach" wire a constant 8v current
with the key switched on. Is this correct(pardon my ignorance)? How does the tach work? I was going to connect this wire to the tach output on the MSD or the trigger wire from the SDS. <hr></blockquote>
I'm not sure about the 8v constant. Is that with just the key on or with the key on and the car running? If it was with the car running, then the 8 volts might be an "average" value that your meter is reading of the signal pulses coming from the ignition. Typically, a tach requires an ignition signal (like the tach output on the MSD or the trigger wire on the SDS.) How the factory Porsche tach works, I have no clue.
Rob
with the key switched on. Is this correct(pardon my ignorance)? How does the tach work? I was going to connect this wire to the tach output on the MSD or the trigger wire from the SDS. <hr></blockquote>
I'm not sure about the 8v constant. Is that with just the key on or with the key on and the car running? If it was with the car running, then the 8 volts might be an "average" value that your meter is reading of the signal pulses coming from the ignition. Typically, a tach requires an ignition signal (like the tach output on the MSD or the trigger wire on the SDS.) How the factory Porsche tach works, I have no clue.
Rob
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I removed my instrument panel to fix the low light problem and upon reinstall my tach didn't work, I found that one of the ribbon cable plugs behind the instrument panel was not connected fully.........just a thought.