tachometer problem
- Thread starter mickeypowa
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OK so I took a look at my olds tach and it looks like pin 4 and 10 are the ones you want to add a resistor to. I've never tested this tach so I'm not sure if it works but it looks like I have 120K ohms across pins 4 and 10 and same when I measure the quartz which is that silver resistor looking component. So it confirms that 4 and 10 are the correct pins as mentioned in that link I posted earlier. Please let me know if I can help further. Also it looks like someone added a resistor across pins 1 and 9 I'm not sure why but it's there. If you have access to a multimeter you can check the quartz and it should be in the 200K ohms area. You'll want to make sure that that is the problem.
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ok thank you very much for your answer !
I have the same tachometer ! I have tested the resistance between the 2 sides of the quartz and I get 243 kohms.
Between the pins 4 and 10, I also get 243 kohms.
It seems more or less good, I don't know if putting a 200 kohms resistor would change my problem.. :/
I have the same tachometer ! I have tested the resistance between the 2 sides of the quartz and I get 243 kohms.
Between the pins 4 and 10, I also get 243 kohms.
It seems more or less good, I don't know if putting a 200 kohms resistor would change my problem.. :/
No problem, glad i could help, if that's the case then its not your resistor pack...The next step would to check your voltage to the tach can you check that 12V is going to the ignition tab within the gauge pod? Check the tach wire from the dist as well...check your ground on the pod too make sure there's continuity to ground.
I will check all that again as soon as I can.
But I'm pretty sure I get power because the needle move at ignition.
I should check the ground but I don't know how. And the others gauges work and they are sharing the same ground so it's strange..
Maybe the wire going to the distributor but I don't know how to check it too, it should deliver a tension ? And it was working 1 week ago so..
But I'm pretty sure I get power because the needle move at ignition.
I should check the ground but I don't know how. And the others gauges work and they are sharing the same ground so it's strange..
Maybe the wire going to the distributor but I don't know how to check it too, it should deliver a tension ? And it was working 1 week ago so..
You can check the wire to the distributor for continuity by connecting the meter to each end. You can also check its resistance that way. On the ground, check for continuity and resistance to the negative battery cable. Hook one lead to the cluster ground wire and hook the other lead to the negatve battery cable terminal.
What Texas said, try all the obvious things first, it could be the ground, it could be the gauge pod flexible circuit too, they are very flimsy and do break, the copper traces are pretty big so it's easy to trace the circuit. I would make sure all the wires and connectors that make the tach work have continuity. Just put the beep feature on your multimeter and start checking wires. Also be sure you disconnect the battery before you start checking wires.
Hi guys ! Thanks for your replies.
So I checked the ground pin of the plug with the multimeter and it's good, I get 0 resistance with the negative part of the battery.
The ignition power pin is good, I get 12.7V when I turn the key.
I tried to check the wire at the distributor but I don't know which one is it, here is photos (the top of the photo is on the left sorry) :
There is one plug with one big red wire and one plug with 3 littles wires (red black brown), and another 3 wires connecting directly (red brown black).
I see only 2 possibilites for my problem, am I right ? :
- the wire of the distributor is not good (but I don't think it's that because it was working perfectly 1 week ago)
- the tach doesn't work anymore (due to a wrong manipulation of me ??), maybe the part of the tach leading to the distributor wire is broken ? Even if I don't see anything special on the board...
So I checked the ground pin of the plug with the multimeter and it's good, I get 0 resistance with the negative part of the battery.
The ignition power pin is good, I get 12.7V when I turn the key.
I tried to check the wire at the distributor but I don't know which one is it, here is photos (the top of the photo is on the left sorry) :
There is one plug with one big red wire and one plug with 3 littles wires (red black brown), and another 3 wires connecting directly (red brown black).
I see only 2 possibilites for my problem, am I right ? :
- the wire of the distributor is not good (but I don't think it's that because it was working perfectly 1 week ago)
- the tach doesn't work anymore (due to a wrong manipulation of me ??), maybe the part of the tach leading to the distributor wire is broken ? Even if I don't see anything special on the board...
It looks to me like the tach wire is disconnected at the distributor cap. It should plug in right next to the big red or pink wire. The wire should be white I think. Look for a loose connector right in that vicinity.
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