94 regal speedometer and tach quit working

11-21-2017, 08:40 PM
HGello, I have a 94 regal and after replacing the battery the speedometer and tach stopped working but the fuel, volt, oil pressure and temp gauges still work...what could possibly be the problem...fuses are all good.....Thanks

Tech II
11-21-2017, 10:53 PM
Are both of them "pinned"?

By that I mean, are the rotating indicators, underneath the PIN that kind of represents the starting position?

Sometimes, when you disconnect/reconnect a battery, and you leave the key in the "on" position, those indicators will rotate, clockwise 360 degrees and get stuck under the pin....now when you start the car, those indicators can't rotate clockwise because the pin is in the way...

11-22-2017, 01:44 AM
battery was replaced but ignition was turned off on both cars when I hooked up the cables

Tech II
11-22-2017, 01:39 PM
Well, the speedometer, and Tach are two different circuits, that should not be affected by just replacing a battery, properly....

About the only way to know for sure is to attach a scan tool and read data from the speed sensor and the tach...if you read data from both on the scan tool, then usually the problem is the cluster, or the wiring between the cluster and the ECM.......

11-22-2017, 02:31 PM
Tech II come to think of it, I forgot and left the ignition on when I hooked up the cables. How do I fix this problem?...saw a video of a chrysler with the same problem and they rest the spedo by holding the trip button in, however tha was a digital odometer readout, mine is analog.. Thanks

Blue Bowtie
11-22-2017, 07:14 PM
Have you tried to cycle the power with the ignition switch (without starting) several times?

Tech II
11-23-2017, 12:37 PM
There are several ways to fix this....

One remove the cluster, and remove the clear cover and manually rotate the indicators back CCW......

One trick that I did, with the customer's permission, remove the trim plate that covers the cluster.......drill a hole in the clear cover near the affected gage.....you drill the hole so that when you put the trim back on, the hole is covered by the trim.....now you can sneak a wire in there through the hole with a little hook on the end, and grab the indicator needle and rotate it back, CCW, to the start position......do this with the key out of the ignition....easy peasy lemon squeasy....

11-24-2017, 07:36 PM
Tech II I checked the tach and spedo and they are not pinned, I unhooked battery for an hour hooked it back up and still nothing. Any ideas what else to check? As I said all other gauges work fine.Thanks

11-24-2017, 07:37 PM
Blue bowtie, did as you said and still nothing

Tech II
11-25-2017, 09:36 AM
Well, like I said you would need an OBD I scan tool....if you can read speed and tach data, it's either a cluster, connection, or wiring problem...

I found a wiring diagram....apparently your cluster is made up of two parts....the cluster and auxiliary gages cluster which has your coolant and fuel gage, and "low fuel" indicator....

Did you check your 15a cluster fuse(this powers the tach and speedometer).....the ground for both of these is the same ground for the fuel gage, so the ground is ok....however there is a connection inside the instrument cluster that may be bad....

02-25-2018, 05:19 AM
have the same problem plus i noticed the mileage isn't registering on trip or total mileage numbers

Add your comment to this topic!