Is Your 2006 Chevy HHR Running Rough? The PCM Might Be the Culprit.
If you’re experiencing frustrating issues like a persistent Check Engine Light, erratic engine behavior, poor fuel economy, or even a no-start condition in your 2006 Chevrolet HHR, the problem may lie with its most critical component: the Powertrain Control Module (PCM). As the central computer of your vehicle, the PCM is responsible for managing everything from fuel injection and ignition timing to transmission shifting and emissions control. When it begins to fail, it can cause a cascade of problems that are often difficult to diagnose.
A failing PCM doesn’t just affect performance; it can leave you stranded. Symptoms can start small—a slight hesitation or a random warning light—but can quickly escalate to major drivability issues. Instead of guessing which sensor to replace next or spending a fortune on diagnostic fees, address the core of the problem with a reliable, correctly programmed replacement PCM.
From the Diagnostic Bay
We had a 2006 HHR come into the shop with a classic intermittent no-start condition. The owner had already replaced the battery, alternator, and even the fuel pump on the advice of another mechanic. The vehicle would run fine for days, then refuse to start for no apparent reason. After connecting our scanner, we noticed communication with the PCM was dropping out randomly. We checked the power and ground circuits to the module, and they were solid. The issue was internal to the PCM itself; heat cycles had caused a hairline crack in a circuit board trace. A replacement, correctly programmed 2006 HHR PCM had the vehicle running reliably within an hour, solving a problem that had plagued the owner for months and cost them hundreds in unnecessary parts.
Common Symptoms of a Failing 2006 HHR PCM
- ✔ Check Engine Light: The light is illuminated, often with communication-related error codes (U-codes) or multiple, seemingly unrelated sensor codes.
- ✔ No-Start or Hard Starting: The engine cranks but refuses to start, or takes an unusually long time to fire up, either hot or cold.
- ✔ Poor Engine Performance: You may notice a significant loss of power, hesitation during acceleration, or rough idling.
- ✔ Reduced Fuel Economy: A faulty PCM can’t efficiently manage the engine’s fuel delivery, leading to a noticeable drop in MPG.
- ✔ Erratic Transmission Shifting: The PCM also controls automatic transmission functions, so you might experience harsh shifts, delayed engagement, or getting stuck in a single gear.
- ✔ Stalling: The engine may stall unexpectedly while driving or when coming to a stop.
The Direct-Fit Solution: Programmed and Ready to Install
This isn’t just a generic, off-the-shelf part. This is a Powertrain Control Module, service number 12599714, that is professionally programmed specifically for your vehicle. We use the Vehicle Identification Number (VIN) you provide at checkout to flash the module with the latest, most up-to-date software directly from General Motors. This critical step ensures that the PCM communicates perfectly with your HHR’s engine, transmission, and all other onboard systems, just as the original did from the factory.
By programming the unit before shipment, we eliminate the need for an expensive trip to the dealership for programming. This makes the installation process straightforward for a competent DIY mechanic or any professional repair shop. It’s designed to be a plug-and-play solution to get you back on the road quickly and confidently.
Installation is Straightforward
On the 2006 Chevrolet HHR, the PCM is located in the left-hand (driver’s side) rear of the engine compartment. The replacement process typically involves:
- Disconnecting the vehicle’s battery.
- Unplugging the electrical connectors from the old PCM.
- Unbolting and removing the old module.
- Bolting the new module in place and reconnecting the electrical connectors.
- Reconnecting the battery.
In some cases, a security relearn procedure may be necessary after installation, which can often be done without special tools. This procedure pairs the new PCM with your vehicle’s anti-theft system.
Guaranteed Compatibility
This module is a direct replacement for a range of vehicles and service numbers. Please verify that your vehicle and original part number are listed below. This unit is compatible with service numbers: 12599714, 12589998, 12597329, 12600882, 12600883, 12605766, and 12605765.
This part will fit the following vehicles with the specified options:
- 2006 Chevrolet HHR: Electronic Control Module; (LH rear engine compartment), 2.2L
- 2006 Chevrolet Cobalt: Electronic Control Module; (LH front engine compartment), 2.2L (VIN F, 8th digit)
- 2006 Pontiac Pursuit: Electronic Control Module; (LH front engine compartment), 2.2L
- 2005 Chevrolet Cobalt: Electronic Control Module; (LH front engine compartment), with ID 12589998
- 2005 Pontiac Pursuit: Electronic Control Module; (LH front engine compartment), with ID 12589998
Frequently Asked Questions
Do I need to do any programming after I receive the module?
No. We program the module to your vehicle’s VIN before it ships. It will arrive ready for installation. In some cases, a simple key relearn or security relearn procedure is required, which can be performed by the end-user without special tools.
Where do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit Vehicle Identification Number (VIN). We cannot ship your part until we receive this information, as the programming is essential for the part to function.
Is this a brand new part?
This is a high-quality, tested, and verified OEM part that has been prepared for your specific vehicle. Each unit is programmed with the latest GM software and inspected to ensure it meets or exceeds original factory performance.
What if this doesn’t fix my problem?
While a faulty PCM is a common cause for the symptoms listed, we always recommend a proper diagnosis by a qualified mechanic. If you’ve installed the part and it does not resolve your issue, please contact us to discuss our return policy and warranty options.
How do I find my original part number?
The service number is printed on a sticker on your original PCM. You can compare this number to the compatible service numbers listed in this description to ensure you are ordering the correct part for your vehicle.