For automotive enthusiasts and owners of classic General Motors vehicles, the Actron CP9110 OBD I code scanner is a valuable tool. This scanner, though an older model, is specifically designed to read the On-Board Diagnostics I (OBD I) systems prevalent in pre-1996 vehicles. However, connecting this scanner to certain GM models, particularly those from the mid-90s, can present a unique challenge. This article delves into how to effectively use your Actron CP9110 with your classic GM car, focusing on a practical solution for the slightly more complex OBD 1.5 systems found in some models.
Understanding the nuances of OBD systems is crucial when diagnosing your vehicle. OBD I was the first generation of standardized on-board diagnostics, used primarily in vehicles before the 1996 mandate for OBD-II. GM vehicles, particularly in the 1994 and 1995 model years, sometimes feature what’s known as OBD 1.5. This hybrid system uses the OBD-II style 16-pin connector but still communicates using OBD I protocols, creating compatibility issues with standard OBD I and OBD II scanners.
The Actron CP9110 is specifically engineered for OBD I, making it ideal for many older GM vehicles. It excels at reading diagnostic trouble codes (DTCs) from the engine and transmission control modules, helping you pinpoint issues quickly and efficiently. However, the standard cable included with the CP9110 might not directly connect to the OBD 1.5 system in vehicles like the 1995 Pontiac Bonneville, which, while OBD I compliant in terms of data protocol, utilizes the OBD-II style connector.
The primary challenge arises from the connector incompatibility. The CP9110 typically comes with an OBD-II cable, which physically fits the 16-pin connector in OBD 1.5 cars. However, the wiring configuration is different, preventing proper communication. Actron did produce a specific cable, the CP9115, designed to bridge this gap. Unfortunately, the CP9115 cable is notoriously difficult to find today, often being discontinued or sold at inflated prices due to its rarity.
Facing this predicament, resourceful car owners have devised a clever DIY solution: modifying a readily available OBD-II cable to be compatible with the OBD 1.5 wiring. This method, popularized within online automotive communities, allows you to create a CP9115 equivalent cable at a fraction of the cost, ensuring your Actron CP9110 can effectively communicate with your 1994 or 1995 GM vehicle.
The core of this solution involves taking a standard, inexpensive Actron OBDII 3.0 cable (often the CP9115 cable is mislabeled or unavailable, but this standard OBDII cable is easier to source and serves as the base) and performing a simple wiring modification. By cutting and splicing the wires according to a specific diagram, you can reconfigure the cable to correctly interface with the OBD 1.5 system.
Here’s a simplified guide to creating your own CP9115 equivalent cable:
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Obtain an Actron OBDII 3.0 Cable: Purchase a standard 6-foot Actron OBDII 3.0 cable. These are commonly available online and at auto parts stores.
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Cut the OBDII Cable: Carefully cut the OBDII cable in half. This will give you two ends to work with for splicing.
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Prepare Four Conductor Wire: Acquire a length of four-conductor wire. Telephone wire can be used in a pinch, but slightly heavier gauge wire is recommended for better durability and signal integrity.
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Splice According to the Diagram: Using the wiring diagram provided below, carefully splice the four-conductor wire between the cut ends of the OBDII cable. Ensure each wire is connected to the correct pin according to the diagram to guarantee proper communication.
Components You’ll Need:
- Actron OBDII 3.0 Cable (CP9115 compatible replacement)
- Four-Conductor Wire (telephone wire or similar)
- Wire Strippers/Cutters
- Splicing connectors or soldering iron and solder
- Electrical tape or heat shrink tubing
Step-by-Step Cable Building Process:
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Study the Wiring Diagram: Thoroughly understand the wiring diagram before beginning. Identify which wires need to be connected and in what order.
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Prepare the Wires: Strip the ends of the wires on both the cut OBDII cable and the four-conductor wire.
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Connect the Wires: Following the diagram, connect the corresponding wires using your chosen splicing method. Ensure a secure and reliable connection for each wire. If soldering, ensure clean solder joints. If using connectors, crimp them tightly.
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Insulate Connections: Insulate each connection point with electrical tape or heat shrink tubing to prevent shorts and protect the wiring.
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Test the Cable: Once completed, carefully test your homemade cable with your Actron CP9110 scanner and your OBD 1.5 GM vehicle. Ensure the scanner powers up and is able to read diagnostic codes.
Testing Your DIY Cable
After constructing your cable, proper testing is crucial. Connect the Actron CP9110, with the appropriate GM OBD I cartridge (typically CP9111), to your vehicle using your newly crafted cable. Turn on the scanner and follow the manufacturer’s instructions to initiate a diagnostic scan. If successful, the scanner should power up, recognize your vehicle’s system, and allow you to read trouble codes.
Alternatives to DIY Cable Construction
While the DIY cable is a cost-effective and satisfying solution, there might be alternative avenues. Occasionally, CP9115 cables or compatible aftermarket cables may surface online on auction sites or specialty auto parts vendors. It’s also worth checking online forums and communities dedicated to classic GM vehicles, as members might offer pre-made cables or point you towards suppliers. As mentioned in the original forum post, there were some vendors who bought out Actron stock and might still have CP9115 or similar cables available, though their availability is not guaranteed and information may be outdated.
Conclusion
The Actron CP9110 OBD I code scanner remains a powerful tool for diagnosing classic GM vehicles. While the connector and communication nuances of OBD 1.5 systems in certain 1994-1995 models can pose a hurdle, the DIY cable solution provides a reliable and affordable way to bridge this gap. By creating your own CP9115 equivalent cable, you can unlock the full diagnostic capabilities of your Actron CP9110, empowering you to maintain and troubleshoot your cherished classic GM car with confidence. This hands-on approach not only saves money but also deepens your understanding of your vehicle’s diagnostic systems.
