Service ESC in Chevy Malibu: Common Reasons and Fixes

Whenever your vehicle has a warning light or message on the dash, it's important to make sure that everything is safe before you keep on driving. The Service ESC message usually appears in the Chevy Malibu because one of the Electronic Stability Control (ESC) modules is failing. However, there is one common problem with the 2019-2021 Malibu models that is worth more attention.

Service ESC message highlights

• Common reasons:a ton of reasons including ABS sensors, steering wheel angle sensor, throttle, etc.
• How to fix:read the codes in all control modules to make the conclusion
• Possible consequences:stability of the car may be affected, safety may be affected
• Priority level:Medium
• Can you drive?Carefully
• DIY repair:Possible but complicated
• Repair price range:$150-$800

2019-2021 Malibu Service ESC and multiple lights

In 2019, there was a major update of the ninth generation of the Malibu and Chevy added new engines. Engineers also had to do something with the wiring and connection modules and they screwed up. There are at least two very serious problems that can cause Service ESC warnings and also a dozen other warnings and lights.

Here are the issues:

1) Failing connection between the Electronic Brake Control Module and Power Steering Control Module. There is a so-called HSCAN BUS that connects the modules and it can fail to provide them with proper connection. There is a service bulletin number 21-NA-220 that covers this.

2) Engine harness chaffing against transmission. This problematic spot is located right below the Electronic Brake Control Unit. There is a wire that can rub on the top of the transmission and eventually lose connection. This is described in yet another service bulleting by GM - 19-NA-225.

So, these are the two common problems, and the second one you can even check on your own. If you know where the Electronic Brake Control Unit is located, you can easily locate the engine wiring harness below this unit. Get a proper light and see if part of that harness rubs against the transmission. Just reposition that harness to avoid issues.

But if the problem has already started, you will need professional help to check and maybe change the affected wires.

Ninth-gen Malibus are quite mysterious. For example, I wrote an article about start-stop deactivation and it got tons of messages with side questions that I'm going to cover in a series of special articles.

Battery issues and Service ESC

Another problem that is more than possible is the issue with the battery. A modern car is just like a gadget - it's fully dependent on the battery voltage. If the battery is low, the control modules start freaking out and eventually fail to communicate with each other. Even if the battery managed to start the engine and the alternator kicked in, the problem may persist.

If you see the Service ESC message in your Malibu, one of the most common problems is the dying battery.

Here's how you can check it:

• take a multimeter and set it to measure volts (DC);
• locate the battery under the hood of your car;
• without starting the engine, measure the voltage on the battery - it should be about 12.5 volts;
• ask someone to start the car and keep the multimeter connected to the battery posts;
• when the engine is cranking, the voltage shouldn't drop lower than 12 volts;
• if it's much lower, the battery is weak and needs replacement or at least recharging;
• any battery older than 5 years may need replacement once you notice any symptoms of low voltage;
• when the engine is started, check the voltage on the battery again - it should be over 14 volts.

If you want to replace the battery with a new one, make sure it's of the same size and has the proper cranking amps. Otherwise, you may cause some additional problems with your vehicle.

If the battery is the culprit, all you need to do is to replace it with the new one or recharge it. Then, start the engine, let it work for some time, and see if the Service ESC message disappeared. If it didn't, you may need to take your car in for an inspection.

What are some other culprits of the Service ESC error?

I believe that the listed above problems cover about 80% of cases when you see the Service ESC message in your vehicle. But the remaining 20% is still important.

So, first of all, you need to understand what is engaged in the ESC. If your car doesn't show any other warning lights and messages, you may consider that it's all about one of the Electronic Stability Control modules.

Here's what it covers:

• ABS - the anti-lock brake system is one of the key units of the ESC and whenever it malfunctions, you will see the Service ESC message on the dash of your Malibu.
• Steering wheel sensor - the ESC can't work if the control module doesn't know the position of the steering wheel, so it's another serious thing to check.
• Yaw rate sensor - this is the complex sensor that measures how far is your car from the predicted traction. I've never heard that it can be faulty unless physically damaged.
• Lateral acceleration center - another important part that gives information about any lateral movements of the car to the control module.
• The ESC control unit - finally, there is the computer that gathers information from all the sensors and makes conclusions. Also, it sends signals to braking systems and throttle if needed.

In some vehicles, ESC also uses the throttle position sensor and several engine systems but I'm not sure it does that in the Malibu. Anyway, the system is quite complex and has a lot of weak links that may have problems with wiring, and connection, or just develop some glitches that prevent it from working properly.

Unfortunately, in most cases, you can't check these sensors manually without proper equipment and also some knowledge of how to use them.

Proper inspection - will your scanner help?

Whenever you get a strange warning light or error message, you may happily get the OBD2 scanner out of your glovebox and insert it into the diagnostic port with a victorious facial expression. But you shouldn't get too happy as of now because the problem isn't solved yet.

The majority of affordable scanners only work with P-codes (powertrain error codes that start with P and are stored in the ECU). While the Service ESC message will most likely pop up because of some other problems. The majority of the codes may be stored in other modules and the scanner will never get them.

So, there are two solutions, in this case:

• you may use a professional scanner that costs a fortune but reads all available codes in your car;
• or you may go to a trusted repair shop or to the dealership and pay about $150 for diagnostics.

If you eventually get the set of codes, you will be able to check the service bulletins that I linked at the beginning of this article and see what exact problem you have. Or the codes may point you directly to the malfunctioning module in your vehicle.

If you see a huge number of codes stored in different modules, you should look at the bulletins linked above or think about the battery health. If the codes are single or maybe there are 2-3 related codes, then there is a certain issue that you can locate by googling those codes.

Want to remind you that we are also waiting for the vacuum pump recall for the Malibu and will update you on the dedicated page on the blog.

Can you drive with Service ESC in your Malibu?

If you only see the Service ESC message and there are no other symptoms or problems, you can safely drive. But still, you should remember that your Electronic Stability Control doesn't work and your car may go to a skid.

So, if the road is slippery or you are driving at high speed, you should be careful. The behavior of your vehicle may seriously change in such conditions and it may make you eventually lose control over the car.

If there are other issues like losing power, stalling, other lights on the dash, etc., you should stop the car safely as soon as possible. In the majority of cases, it's worth paying for a tow truck but staying safe.

Usually, when wiring is freaking out, you may get limp mode or the engine may stall unexpectedly. In these cases, you risk getting into car accidents due to losing control over your Chevy Malibu. So, be careful!

If you have any experience with the "Service ESC" error message in the Malibu, please share in the comments below and let other Chevy owners know!