Why These Instrument Clusters Are Going Crazy

Many GM vehicle owners have reported a common issue with their instrument clusters. They've noticed their instrument cluster acting strange. It's as if the cluster has a mind of its own.

cluster troubleshooting

Image Credit: Kammeron Bennetts

The most common erratic behavior drivers have noticed include:

  • RPM gauge showing rpms increasing and decreasing randomly
  • Instrument cluster lights flickering
  • Speedometer jumping around erratically
  • Gauge indicators moving without any driver input
  • Doors locking and unlocking without being prompted
  • ABS light and/or check engine light coming on for no clear reason
  • Traction control working intermittently
  • Difficulty starting the vehicle

These malfunctions can be frequent enough to affect the driver's ability to focus and operate the vehicle. If you're dealing with this particular issue, try to figure out the root cause of the issue and then get it fixed ASAP.

You can start by going over the most common causes of erratic instrument cluster activity:

1. Weak Battery Connection

battery voltage

Weak battery connections will cause issues with the vehicle's electrical system. The battery won't have enough power for all the electrical components, including the instrument cluster.

The first thing you want to check is the connectors. There may be a loose connection that causes the electrical system to go haywire. If you've noticed your instrument cluster going crazy after you've driven on a bumpy road, a loose connection may be the cause.

If you find that the connectors are loose, tighten them. This may be enough to fix the problem. What if the connectors are tight enough? The terminals may be too dirty.

There are two ways you can check to see if your car's battery terminals need to be cleaned. First option, you can check the voltage on the battery cable connectors. Then check the voltage directly at the battery post. If there is any voltage drop, one of the connectors is not getting a good connection. In that case, it may be dirty terminals that are causing a voltage drop. Try cleaning up the connections and see if that sorts out the problem.

The second option is to look for sulphate on the battery terminals and connectors. Sulfate is a whitish bluish crystalline powder that can build up on battery terminals and posts. It is a sign that either there is a bad connection, or that the battery has gone bad. 

Sometimes the battery itself is the culprit. This issue will show up in a similar way to battery terminal issues mentioned above. If you find that your battery terminals aren't dirty, try jump starting the vehicle. Use a vehicle with battery that you know is strong. You can see if you have the same problem when your car is running on the good battery at a full charge.

If your battery terminals are clean and the battery is heathy, the next thing you should check is your alternator. It could be that it isn't generating enough voltage for the battery.

2. Bad Module

Sometimes when a module on a vehicle gets physically damaged, it can cause a short. That will lead to the instrument cluster acting erratically. In this case, the instrument cluster is fine, but the module needs to be replaced.

This is common with ABS modules, parking assist modules, and any other module that's exposed to the external elements.

3. Bad Wiring

cluster wiring

Image Credit: Kammeron Bennetts

Wiring in your vehicle carries the electrical current. The wiring has to be in good condition to do its job well. So when one of these wires goes bad, your instrument cluster can start acting strange. Check the following wires for damage:

  • Ground wire: It's common for the ground wire to get corroded. That could lead to intermittent power flow. You can try splicing your ground wire. Here's a video tutorial for Chevy Silverado trucks and GMC Sierra trucks.
  • Relay: One of the components that controls the electrical current on your vehicle is a relay. A bad relay can cause voltage problems and therefore an instrument cluster malfunction.
  • Wire connectors: If you have corroded wire connectors, the corrosion could cause electrical problems.

4. Defective Stepper Motor

It's possible that the electrical system is fine, but it's the instrument cluster itself that's the issue. In fact, some GM vehicles built between 2003 and 2007 came with defective stepper motors. There was a class action lawsuit, but there wasn't a formal recall. So if your GM vehicle was built between 2003 and 2007, chances are you're dealing with a bad stepper motor. If your vehicle is older or newer, it's still possible that you're dealing with this issue.

If the instrument cluster is the only part in your vehicle's electrical system that's acting up, you may want to get it checked out. At ISS Automotive, we repair instrument clusters. You don't have to find an instrument cluster repair shop near you because we fix instrument clusters from all over the nation. All you have to do is remove the instrument cluster from your vehicle and then ship it to us. We'll start fixing it within 24 hours of receiving it.

Please contact us if you have any questions about our instrument cluster repair services.