Is Your Saturn SKY Shifting Erratically?
If you’re experiencing harsh shifting, delayed engagement into gear, or a transmission that seems to have a mind of its own, a failing Transmission Control Module (TCM) is the most likely culprit. The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every shift with precision. When it fails, it can cause a cascade of frustrating and potentially damaging issues for your 2007-2010 Saturn SKY, Pontiac Solstice, or other compatible GM vehicle. Symptoms often start small but can quickly escalate, leaving you stranded or facing a check engine light that won’t go away.
From the Diagnostic Bay
We had a 2008 Pontiac Solstice GXP come into the shop with a complaint of getting stuck in 3rd gear (limp mode) and a flashing gear indicator. The customer had already replaced two transmission solenoids based on a generic code reader, but the problem persisted. After a quick scan with a professional tool, we pulled a U0101 (Lost Communication with TCM) code. Instead of jumping to a costly transmission replacement, we inspected the TCM on the left front frame rail. We found slight corrosion on the connector. After confirming the wiring was good, we knew the internal electronics of the module had failed. We installed one of our pre-programmed TCMs, matched to the car’s VIN, and had the car shifting perfectly in under an hour. The customer saved thousands by correctly diagnosing the electronic failure instead of a mechanical one.
Symptoms of a Failing Transmission Control Module
- ✔ Check Engine Light: Often accompanied by transmission-specific codes like P0700, P0751, P0756, or communication codes like U0101.
- ✔ Erratic Shifting: Harsh, slamming shifts, delayed engagement from park to drive, or slipping between gears.
- ✔ Limp Mode: The transmission may get stuck in a single gear (usually 2nd or 3rd) to prevent further damage.
- ✔ Poor Fuel Economy: Inefficient shifting directly leads to the engine working harder and consuming more fuel.
- ✔ Warning Lights: You may see a “Service Engine Soon” light or other transmission-related warnings on your dashboard.
- ✔ Inability to Shift: In severe cases, the vehicle may not shift out of Park at all.
The Direct-Fit, Pre-Programmed Saturn SKY TCM Solution
This isn’t just a part in a box; it’s a complete solution. This listing is for a replacement TCM (part number 24239785, which supersedes 24235224 and YLMU) that is professionally programmed to your vehicle’s specific Vehicle Identification Number (VIN). This is a critical step that cannot be skipped. An unprogrammed module will not communicate with your vehicle’s other computers, leaving your car inoperable. By providing us with your VIN during checkout, you receive a unit that is truly plug-and-play. We load the latest, most stable software calibration from General Motors, ensuring optimal performance and longevity. This process eliminates the need for an expensive trip to the dealership for programming with a Tech 2 or MDI scan tool.
Complete Vehicle Fitment Information
This module is a direct replacement for vehicles equipped with the specified part numbers. Please verify your part number or consult your mechanic if you are unsure. This part is confirmed to fit the following applications:
- Saturn SKY: 2007, 2008, 2009, 2010 (Transmission; located on LH front frame rail)
- Pontiac Solstice: 2006, 2007, 2008, 2009, 2010 (Transmission; located on LH front frame rail)
- Cadillac STS: 2007 (Transmission), 2010-2011 (Transfer Case; located on RH dash)
- Cadillac SRX: 2007, 2008, 2009 (Transmission; located on RH front engine compartment)
- Cadillac CTS: 2010 (Transfer Case; located on RH dash) – for IDs 2423522, YLMU, 24239785
Frequently Asked Questions
Do I need to have this module programmed?
No, we handle the programming for you before shipment. This is the main benefit of our service. You must provide your vehicle’s 17-digit VIN at checkout so we can load the correct software. The part will arrive ready for installation.
Where is the TCM located on my 2009 Saturn SKY?
On the Saturn SKY and Pontiac Solstice, the Transmission Control Module is located on the driver’s side (LH) front frame rail in the engine bay. It is a silver box with a large electrical connector. Always disconnect the battery before attempting to replace any electronic module.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating that the TCM has detected a problem and has requested the Check Engine Light to be turned on. While a faulty TCM can cause a P0700, this code is often accompanied by other, more specific codes. This module will fix the issue if the TCM itself is the source of the fault. Proper diagnosis is always recommended.
Is this part the same as an ECM or PCM?
No. The TCM (Transmission Control Module) specifically controls the functions of the automatic transmission. The ECM (Engine Control Module) or PCM (Powertrain Control Module) is the main computer that controls the engine’s functions. They are separate components, though they communicate with each other constantly.
What is the difference between part numbers 24235224 and 24239785?
Part number 24239785 is the newer, updated replacement part from GM for the original 24235224. It often includes hardware and internal software improvements for better reliability and performance. Our modules are based on this improved design and loaded with the latest software for your vehicle.