Is Your Saturn Aura Shifting Erratically?
If you’re dealing with harsh gear changes, a car that won’t shift, or a persistent check engine light, a failing Transmission Control Module (TCM) is the likely culprit. As the transmission’s brain, the TCM dictates every shift. When it fails, it can make your 2007-2009 Saturn Aura feel unreliable and unsafe to drive. Over my 20+ years in auto repair, I’ve seen these T42 modules cause countless headaches, but the fix is surprisingly straightforward.
The Direct Solution: A VIN-Programmed T42 TCM
This isn’t just a replacement part; it’s a complete, ready-to-install solution for your vehicle. We take this OEM-quality module, interchangeable with part number 24235754, and pre-program it to your car’s specific Vehicle Identification Number (VIN). This critical step ensures the module communicates flawlessly with your Aura’s engine and transmission systems right out of the box, eliminating the need for an expensive trip to the dealership for programming.
A Real-World Scenario from My Shop
A customer’s 2008 Saturn Aura came in last week with these exact symptoms…
The car was stuck in 3rd gear (limp mode), and the dash was lit up with a check engine light. The owner was worried about a major transmission rebuild. I pulled the codes and saw P0700 (Transmission Control System Malfunction) and a few solenoid-specific faults. Instead of tearing into the transmission, I checked the TCM. After confirming it was faulty, we installed one of our pre-programmed modules. In under 30 minutes, the codes were cleared, the car was shifting like new, and the customer saved hundreds, possibly thousands, on unnecessary diagnostic time and repairs.
Common Symptoms of a Failing Saturn Aura TCM:
- โ Hard, slamming shifts or delayed gear engagement.
- โ Vehicle stuck in a single gear (known as “limp mode”).
- โ Check Engine Light or Transmission Warning Light is on.
- โ Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid codes are present.
- โ A sudden drop in fuel economy or transmission overheating.
- โ Complete loss of communication with the transmission.
Plug-and-Play Installation: No Dealer Visit Required
This is a repair you can confidently tackle in your own driveway. For the 2007-2009 Saturn Aura, the TCM is located on the front of the left frame rail. The entire process takes less than an hour.
- Safety First: Disconnect the negative terminal from your car’s battery to prevent electrical shorts and help reset the system.
- Locate the Module: Find the TCM on the front section of the driver’s side frame rail.
- Disconnect and Remove: Carefully unplug the electrical connectors. Be gentle with the locking tabs. Then, unbolt the old module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module in place and securely reconnect the electrical harnesses. You should hear a click.
- Final Steps: Reconnect the battery. Start the vehicle and use a basic OBD2 scanner to clear any stored fault codes. Take your Aura for a test drive to confirm smooth shifting.
Frequently Asked Questions about the 2007-2009 Aura Transmission Control Module
- Q: What does VIN programming do?
- A: VIN programming loads your car’s specific software onto the module. This ensures it works perfectly with your engine size, tire ratio, and other factory settings for optimal shift points and performance, avoiding the compatibility issues that come with non-programmed units.
- Q: Is this part difficult to install myself?
- A: Not at all. With basic hand tools, the installation is very straightforward. Locating it on the LH frame rail in the Aura makes it accessible, and our pre-programming means the hardest part (the software setup) is already done for you.
- Q: Will this fix my P0700 trouble code?
- A: Yes, in the vast majority of cases. A P0700 code is a general fault indicating the TCM has detected a problem. Replacing a faulty TCM with this programmed unit is the direct fix for the root cause of that code.
- Q: Do I need to send my old part back?
- A: No, there is no core charge for this module. You can keep your old part, saving you the time and hassle of a return shipment.
- Q: What is the warranty on this module?
- A: This module is backed by our one-year, hassle-free warranty, giving you peace of mind and confidence in your repair.