Restore Peak Performance to Your GMC Safari
Is your 2004 GMC Safari struggling with a persistent check engine light, erratic engine behavior, or a frustrating no-start condition? These are classic signs of a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. Over time, heat, vibration, and age can cause internal components to fail, leading to a host of problems that can leave you stranded. This replacement PCM, part number 89017739, is the reliable, straightforward solution to get your trusted van running smoothly again.
What sets this module apart is our professional programming service. Before we ship your part, we flash it with the latest official GM software updates, tailored specifically to your vehicle using the VIN you provide. This critical step ensures complete compatibility and optimal performance, eliminating the need for an expensive trip to the dealership for programming. It arrives at your door ready for installation, saving you both time and money.
Case Study: A Tricky Diagnosis
I recently had a 2004 Astro van (which shares the same platform as the Safari) in my bay with a very tricky intermittent no-start. The owner had already replaced the battery, alternator, and starter. The engine would crank but wouldn’t fire, and there were no consistent trouble codes. After checking fuel pressure and spark, which were present but weak, I hooked up my professional scan tool. I noticed the PCM would periodically lose communication with other modules. On a hunch, I tapped the PCM casing and the engine immediately stalled. This confirmed an internal fault in the module. A new, pre-programmed PCM like this one solved the problem in under an hour, fixing a gremlin that had plagued the owner for months.
Is Your Safari Showing These Telltale Signs?
A failing PCM can manifest in various ways. If you’re experiencing any of the following, it’s a strong indicator that your engine computer needs attention:
- ✔ Unexplained Check Engine Light (CEL) illumination.
- ✔ Common diagnostic trouble codes (DTCs) such as P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Poor or declining fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Stalling, stumbling, or hesitation during acceleration.
- ✔ Failure to pass state emissions testing.
A Straightforward Guide to Installation
Installing your new 2004 GMC Safari PCM is a manageable job for a DIY enthusiast. For the Safari and Astro, the module is conveniently located. Always consult a repair manual for your specific vehicle, but here are the general steps:
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On the 2004 GMC Safari, the PCM is typically found in the engine compartment on the driver’s side, near the battery.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old PCM. Inspect the connectors for any corrosion or damage and clean them if necessary.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount the new module securely onto the bracket and re-fasten the bolts.
- Reconnect Everything: Plug the wiring harnesses firmly back into the new PCM. Reconnect the negative battery terminal.
- Perform Security Relearn: After installation, you will need to perform a security relearn procedure (often called a CASE relearn or Passlock relearn) to sync the new PCM with your vehicle’s anti-theft system. This procedure can typically be done without special tools and instructions are readily available online or in your owner’s manual.
Verified Compatibility Across a Wide Range of GM Vehicles
This versatile PCM is a direct fit for a large number of 2004 GM trucks, vans, and SUVs, as well as select performance cars. Please verify your part number (89017739 or 12586243) and vehicle from the list below to ensure proper fitment. This module is compatible with:
AVALANCHE 2500 04 (LH front under battery)
BLAZER S10/JIMMY S15 04 (RH front engine compartment)
CTS 04-05 V-Series (RH engine compartment, ID 12586243)
CORVETTE 04 (RH engine compartment, ID 12586243)
ENVOY XL/XUV 04 5.3L (next to air box)
EXPRESS 1500/2500/3500 VAN 04 (LH rear engine compartment)
GTO 04 (main, LH engine)
RAINIER 04 5.3L (next to air box)
S10/S15/SONOMA 04 (RH front engine compartment)
SAFARI (GMC) 04 (LH front by battery)
SAVANA 1500/2500/3500 VAN 04 (LH rear engine compartment)
SIERRA 1500 PICKUP 04 4.3L (LH front under battery)
SIERRA 2500/3500 PICKUP 04 8.1L Gasoline (LH front under battery)
SILVERADO 1500 PICKUP 04 4.3L (LH front under battery)
SILVERADO 2500/3500 PICKUP 04 8.1L Gasoline (LH front under battery)
SSR 04 (next to air box)
SUBURBAN 2500 04 8.1L (LH front under battery)
TRAILBLAZER EXT 04 5.3L (next to air box)
YUKON XL 2500 04 8.1L (LH front under battery)
Frequently Asked Questions
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential for us to program the PCM with the correct, vehicle-specific software and calibrations from GM. This ensures perfect communication with your engine, transmission, and other onboard systems, making the installation process plug-and-play.
Is any additional programming required after installation?
While we handle the main programming, you will need to perform a security relearn procedure (also known as a CASE relearn or crankshaft position variation learn) after you install the module. This syncs the new PCM to your vehicle’s anti-theft system and crankshaft sensor. It’s a simple procedure that typically takes 10-30 minutes and does not require a special scan tool.
Will this fix my vehicle’s specific problem?
This PCM will correct issues directly caused by a faulty module. While the symptoms listed are common for PCM failure, it’s crucial to ensure your vehicle has been properly diagnosed. Other issues, like bad sensors or wiring problems, can mimic PCM failure. We recommend a thorough diagnosis before ordering.
Is this a new or used part?
This is a high-quality, fully tested recycled OEM part. Each unit undergoes a rigorous inspection and functional testing process to ensure it meets or exceeds original factory standards. We then program it with the latest software for your vehicle, providing a reliable and cost-effective solution.