Is your 2006-2007 Saturn ION suffering from frustrating and unpredictable shifting? If you’re dealing with harsh gear changes, getting stuck in limp mode, or seeing that dreaded check engine light, you’re not alone. These are classic signs of a failing Transmission Control Module (TCM). Instead of risking a costly trip to the dealership for diagnostics and programming, take control of the repair with this OEM-quality, VIN-programmed T42 Transmission Control Module, part number 24234503.
As the electronic brain of your automatic transmission, the TCM is responsible for every shift. When it fails, it can cause a cascade of problems that make your vehicle unreliable and unsafe to drive. This replacement module is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN. This ensures perfect communication with your car’s other computers right out of the box, restoring the smooth, efficient performance you expect. No extra programming, no dealership visits—just a straightforward, reliable fix.
From the Diagnostic Bay: A Common Saturn ION Case
I remember a 2007 Saturn ION that came into the shop a few months back. The owner was frustrated because the car would randomly refuse to shift past second gear, but the problem was intermittent. Another shop had quoted him for a full transmission rebuild, suspecting internal damage. After hooking up my scan tool, I saw a P0700 (Transmission Control System Malfunction) and a few intermittent solenoid circuit codes. Experience has taught me that on these GM platforms, intermittent electrical faults often point away from the transmission itself and toward the TCM. We swapped in a VIN-programmed module, and the problem was solved in under an hour. It’s a perfect example of how the right part can save you thousands in unnecessary repairs.
Is Your Saturn ION Showing These Red Flags?
A failing TCM isn’t subtle. If you notice any of these issues, it’s time to consider a replacement. Overlooking these symptoms can lead to more significant transmission damage down the road.
- âś” Harsh, slamming, or erratic gear shifts.
- âś” Vehicle is stuck in one gear (often called ‘limp mode’).
- âś” Delayed engagement when shifting from Park to Drive or Reverse.
- âś” Check Engine Light or Transmission Warning Light is illuminated.
- âś” Diagnostic Trouble Codes (DTCs) are present, especially P0700, P0750, or other solenoid-related codes.
- âś” Poor fuel economy and a feeling of sluggish performance.
- âś” Complete failure to shift gears.
DIY-Friendly Installation in Under 30 Minutes
This repair is well within the reach of a DIY enthusiast. The module is located in the engine bay for easy access. For the 2006-2007 Saturn ION, you’ll find it located behind the driver-side (LH) strut tower.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: Find the TCM behind the LH strut tower. It will have several electrical connectors attached.
- Disconnect and Remove: Carefully unplug the wiring harness connectors. Then, unbolt the old module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed module into place. Securely reconnect the wiring harnesses, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s good practice to use a basic OBD2 scan tool to clear any stored fault codes from the vehicle’s memory. Start the car and enjoy smooth shifting!
Verified Fitment for Your Vehicle
This T42 TCM is the correct, direct-fit replacement for the following vehicle:
- Saturn ION: 2006-2007 (Located behind LH strut tower)
This module also serves as a replacement for a wide range of other General Motors vehicles from 2006-2014, including models like the Chevrolet Cobalt, HHR, Impala, GMC Sierra, and Buick LaCrosse. It is interchangeable with part numbers 24242391, 24252114, and others listed in the compatibility chart.
Frequently Asked Questions
What does ‘VIN Programmed’ actually mean?
It means we load your vehicle’s unique 17-digit Vehicle Identification Number (VIN) and the latest GM software onto the module before we ship it. This ensures it works perfectly with your car’s engine computer and other systems, eliminating the need for expensive dealership programming.
Do I need any special tools for this installation?
No special tools are required. Basic hand tools like a socket set to unbolt the module and a flathead screwdriver to help release connector clips are all you should need. An OBD2 scanner is recommended to clear codes but is not strictly necessary for the part to function.
Is there a core charge? Do I have to send my old part back?
No, there is no core charge on this module. You can keep your old part or dispose of it without any hassle or extra fees.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. In many cases, a faulty TCM is the root cause, and replacing it will resolve the issue. However, it’s always best to scan for other, more specific transmission codes (like P0753, P0758, etc.) to confirm the diagnosis.