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Hello,

Thank you in advance for any help.

I was driving the other day and my tachometer stopping working all of a sudden. I have removed the entire gauge cluster to check the contacts--no luck. I don't think there is an individual fuse for tachometer. All other gauges work just fine. I'd rather not pay $500 for a new gauge cluster. Is there a sensor that determines the RPM's? Thank you.

Bryan

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2000gauges.pdf

You can try to ohm out the windings on the tach, then as a quick check for the input, you could try using the ac range on a DVM. I have not tried this before (I have access to a scope) but I would guess that you should measure ac volts while the engine is running. So hook up a meter while the key is on, engine off and note the volt (should be zero), then start the car. You should see voltage at that time. The voltage will not change at you rev the engine, but it should read something.

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2000gauges.pdf

You can try to ohm out the windings on the tach, then as a quick check for the input, you could try using the ac range on a DVM. I have not tried this before (I have access to a scope) but I would guess that you should measure ac volts while the engine is running. So hook up a meter while the key is on, engine off and note the volt (should be zero), then start the car. You should see voltage at that time. The voltage will not change at you rev the engine, but it should read something.

Ohm out the windings? I found a YouTube video of a guy doing it on an air compressor.

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Yes, if you use a DVM, the procedure is the same. Now when you say that you pulled the dash, and checked connections. Are you talking about the main electrical connectors, or did you take the back off and GENTLY tighten all the screws?

Yes, the main connectors. I checked to make sure they were all connected properly an cleaned the contacts.

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If the 2000 is anything like the earlier years, then you need to remove the instrument panel, and then remove the rear circuit bd. There is another bd underneath, it is on this bd that there are several screws that complete the circuit for the different needles. You want to find the 4 directly behind the tach and ohm them out. Use the speedometer for comparison. MAKE SURE YOU USE A DVM, AND NOT A ANALOG METER ( a voltmeter with a needle). The DVM had high enough input impedance so that you will not harm electronic components. A analog meter has a much lower impedance. Also make sure that the screws are tight, (keep in mind that this is a screw going into plastic), do not go star tight, or it will strip.

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  • 4 months later...
2000gauges.pdf

You can try to ohm out the windings on the tach, then as a quick check for the input, you could try using the ac range on a DVM. I have not tried this before (I have access to a scope) but I would guess that you should measure ac volts while the engine is running. So hook up a meter while the key is on, engine off and note the volt (should be zero), then start the car. You should see voltage at that time. The voltage will not change at you rev the engine, but it should read something.

Hi were you successful in fixing the rpm guage? I have the same problem on my 98 es300. RPM is completely at 0 so it seems to be electrical but not completely sure.

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  • 1 month later...
2000gauges.pdf

You can try to ohm out the windings on the tach, then as a quick check for the input, you could try using the ac range on a DVM. I have not tried this before (I have access to a scope) but I would guess that you should measure ac volts while the engine is running. So hook up a meter while the key is on, engine off and note the volt (should be zero), then start the car. You should see voltage at that time. The voltage will not change at you rev the engine, but it should read something.

Hi were you successful in fixing the rpm guage? I have the same problem on my 98 es300. RPM is completely at 0 so it seems to be electrical but not completely sure.

No. I have not had time. I seem to have forgotten about it but, when spring rolls around every little annoyance is going to be fixed.

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2000gauges.pdf

You can try to ohm out the windings on the tach, then as a quick check for the input, you could try using the ac range on a DVM. I have not tried this before (I have access to a scope) but I would guess that you should measure ac volts while the engine is running. So hook up a meter while the key is on, engine off and note the volt (should be zero), then start the car. You should see voltage at that time. The voltage will not change at you rev the engine, but it should read something.

Hi were you successful in fixing the rpm guage? I have the same problem on my 98 es300. RPM is completely at 0 so it seems to be electrical but not completely sure.

No. I have not had time. I seem to have forgotten about it but, when spring rolls around every little annoyance is going to be fixed.

I have finally fixed my rpm guage. Here's how I did it: Basically, you have 2 options. Buy a used cluster off ebay and do a direct swap(Easy route). Keep in mind the mileage is stored in the cluster itself so your car will show the mileage of the new cluster if you decide to get it. Now I did not take that route because I wanted my car to show its original mileage so I decided to repair my cluster. This is indeed a tedious task and I would set aside about 2 hours before you begin. Since my car is a 98 I had to get a 97-98 donor cluster to do the repair. Your car is a 2000 so you will need to get the 00-01 cluster. Do not get the 97-98 or the 99 cluster even though they look exactly the same, they do have slight differences. You can get one off ebay for about $100 or maybe cheaper. Mine was $80. Anyway, after the donor cluster arrives set it aside. You will now take your original cluster and proceed to take it apart. I stress be very careful not to damage it and take your time. Here are the steps:

1) Remove the black plastic cover in the front. They are just small tabs that you press down and it should easily pop out.

2) Once you do that, remove the secondary cover its below the black cover. It is also held by tabs.

2) Turn it around and remove the white cover hiding the main board. It is just 4 screws. Once the screws are out, lift it up.

3) Remove the main board. There is ribbon that you will need to remove by lifting the black tab that is holding it in place. Once the ribbon is out just lift it up.

4) Now proceed to take out every screw in the back. BE CAREFUL not to mismatch the screws because they are different sizes so basically remember which hole each screw came out of. **YOU DO NOT NEED TO TAKE OUT THE BULBS!

5) Now turn it around and there is one screw on the top left hand corner, I believe by the temp guage. Once that is removed, you can simply open it up to see the guts of the cluster.

6) If you look behind the rpm gauge there is a small circuit board. THIS IS THE CULPRIT!!! You will proceed to remove this board by bending 4 tabs on top that is holding it in place.

Basically what you will do is replace this little circuit board with the circuit board from your donor cluster and put everything back together in the order you took it out. Be sure to bend the tabs back after you put on the new circuit board.

Sorry, I have to say this: I am not responsible if you damage your cluster in this process.

Anyway, I hope this helps and let me know if you are successful. Thanks

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  • 2 months later...

All I have to say is you are awesome and I will be ordering the cluster....Today! Thank you. Although the car is an automatic, it is very important to monitor your RPMs. A mechanic laughed when I told him it was broken and asked why I needed it. If this works, this thread should be "stickyed" at the top. Found one on eBay for $50 after shipping ~80)

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