97+ tachometer works after changing plugs.

[Geonovast]

Mine came UPS, but then again, we didn't get the same one.

[jimoshel]

Asleep at the switch again. Not Fedex. UPS. The guy in the Brown truck. Looks like a nice unit. Got a S10 with auto just waitin for me to try it out on tomorrow. :doh:

[Yesterday's Danish]

Not sure if this will help you but here is the procedure to do a self test on the gauge cluster.

 

Put the key in the ignition and leave in the "OFF" position

Turn the parking lights on (Pull the light switch out (1) click)

Press and hold the "Trip Reset" button and switch the key to the "ON" position

The cluster will "Beep" and begin it's self test. You may remove your finger from the "Trip Reset" button

Watch the pretty lights and needles move around and light up

Flip the turn signals on and verify they are working

Do the same with the headlights and the bright switch

After it is complete and you have verified that all the gauges and lights are functioning, button everything back up!

 

Might tell you if the tach is broken or if the needle is just misaligned.

[JeepcoMJ]

thanks for that info danish! that's now saved in my tech files :D

[Geonovast]

Niiice. I'm certainly going to give that a try tomorrow.

 

I really think the tach is shot though. Sometimes it reads fine, sometimes it's stuck, sometimes it reads high... and sometimes it wiggs out and jumps all over the place. Jumping back and forth between 0 and 4k while maintaining a steady speed, and the needle bounced on our crappy road. It also doesn't default to 0 when the key is off, it usually sticks wherever it was left.

 

It was weird, the first time I drove it after it was installed, I started it up, and the tach jumped up, and settled down about 800, like normal. Then when I switched on the lights, it jumped up to about 1700, and then back down to 800 when I shut them back off. I was not moving or touching the pedal when this happened, and the motor obviously did not change speed.

 

Will it give any error codes if something's wrong?

[Yesterday's Danish]

Not sure if it will dump any codes. Just tried it on my XJ and it went through the test as normal without giving me any code at the end of the test. Then again, my cluster works fine. Only one way to find out.

[Geonovast]

I did the test, and it was a little goofy. All the tach did though, was go to 0, then to 2100, then to 0, then to 2100, then to 0, and went up to about 400 when I shut off the key.

 

Methinks it's dead.

[jimoshel]

Not sure if this will help you but here is the procedure to do a self test on the gauge cluster.

 

Put the key in the ignition and leave in the "OFF" position

Turn the parking lights on (Pull the light switch out (1) click)

Press and hold the "Trip Reset" button and switch the key to the "ON" position

The cluster will "Beep" and begin it's self test. You may remove your finger from the "Trip Reset" button

Watch the pretty lights and needles move around and light up

Flip the turn signals on and verify they are working

Do the same with the headlights and the bright switch

After it is complete and you have verified that all the gauges and lights are functioning, button everything back up!

 

Might tell you if the tach is broken or if the needle is just misaligned.

When doing this test, specifically what do the gauges do? Swing back and forth? Peg and return? Go to a specific position and stay?

[Yesterday's Danish]

The gauges go up to a certain spot, then come back down. It does this ten or so times and the gauges go to various places. The lights on the gauge cluster light up and shut off as well.

[Geonovast]

Here's a thinker for ya guys.

 

I changed the spark plugs today because it would occasionally miss while accelerating in OD. The old plugs didn't look damaged, weren't full of sludge or anything, just old.

 

Now my tach works. The needle's still a little floaty when I hit a bump, but other than that, it seems to be working fine.

 

I don't see how changing the plugs could have done this. :dunno: Any ideas?

[jimoshel]

Did you check your horoscope and see what the relationship between Mars and Jupitor was?

[jimoshel]

Not sure if this will help you but here is the procedure to do a self test on the gauge cluster.

 

Put the key in the ignition and leave in the "OFF" position

Turn the parking lights on (Pull the light switch out (1) click)

Press and hold the "Trip Reset" button and switch the key to the "ON" position

The cluster will "Beep" and begin it's self test. You may remove your finger from the "Trip Reset" button

Watch the pretty lights and needles move around and light up

Flip the turn signals on and verify they are working

Do the same with the headlights and the bright switch

After it is complete and you have verified that all the gauges and lights are functioning, button everything back up!

 

Might tell you if the tach is broken or if the needle is just misaligned.

 

I tried this test on 4 MJ'S and 5 XJ'S. None of the others had a trip reset. Didn't work on any of them. No beep. No meter movement. Nada.

[Geonovast]

Not sure if this will help you but here is the procedure to do a self test on the gauge cluster.

 

Put the key in the ignition and leave in the "OFF" position

Turn the parking lights on (Pull the light switch out (1) click)

Press and hold the "Trip Reset" button and switch the key to the "ON" position

The cluster will "Beep" and begin it's self test. You may remove your finger from the "Trip Reset" button

Watch the pretty lights and needles move around and light up

Flip the turn signals on and verify they are working

Do the same with the headlights and the bright switch

After it is complete and you have verified that all the gauges and lights are functioning, button everything back up!

 

Might tell you if the tach is broken or if the needle is just misaligned.

 

 

I tried this test on 4 MJ'S and 5 XJ'S. None of the others had a trip reset. Didn't work on any of them. No beep. No meter movement. Nada.

 

It'll only work on 97+

[Yesterday's Danish]

:agree:

[jimoshel]

HUMPH. Discrimination.

[Geonovast]

I just ran out and did the test again, and the tach went to 2k, 5k, 6k, 5k, 2k, 0.

 

I had Jeepcomj run the test on one of his and it did the same thing.

 

Could I have somehow "shocked" the tach into behaving better when I changed the plugs?

[jimoshel]

Was yer engine running when U changed plugs?

:roll: < straight face

[Geonovast]

Was yer engine running when U changed plugs?

:roll: < straight face

 

Of course...

 

How else would you change them? :dunno:

[dunl]

I agree.

 

 

 

 

 

Must have been the horoscope. :cheers:

[mythreesons]

Here's a thinker for ya guys.

 

I changed the spark plugs today because it would occasionally miss while accelerating in OD. The old plugs didn't look damaged, weren't full of sludge or anything, just old.

 

Now my tach works. The needle's still a little floaty when I hit a bump, but other than that, it seems to be working fine.

 

I don't see how changing the plugs could have done this. :dunno: Any ideas?

 

Off the top of my pointy little head............ Old plug &/or wire "slightly" shorting a little to ground causing the funny reading on the tach? By changing the plugs, which of course means the wires are moved/wiggled you might have gotten rid of "slight" short. It might have been just enough to barely cause a problem with the tach, but operate "OK" / not noticable until in overdrive. Or in the same arena, cross arcing from one plug wire to another causing the tach signal to go funky?

 

Hmmmmm, electrical problems, gotta love it. :D :fs1: :D :fs1: :D :fs1:

[jimoshel]

On a side note, Has any one ever raised their hood with the motor running,on a really dark night and watched the display? The older the wiring the more colorful the Aura Borealas.

[Keith]

What you are witnessing when you open the hood and see the glow around the wires and plugs is a condition called "corona", there is an electrical field around your ignition wiring. Most people think it is voltage leaking from the plugs or wires but not so, has no negative impact on proper ignition.