1995 GMC S10 Sonoma Won't Read OBD-I Codes with Scanner - ABS and Brake Lights On
I have a 1995 GMC S10 Sonoma with a 4x4 drivetrain. I'm unable to get any diagnostic codes from my OBD-I scanner (commonly referred to as OBD-1.5). The vehicle has a 16-pin connector, and I've tried connecting to pins 4, 5, 6, 9, 12, 13, and 16 — but no readings appear. The scanner shows a '2' response when attempting to communicate. The vehicle also fails to shift gears properly, and both the ABS and brake warning lights are illuminated. I'm looking for suggestions on how to resolve this issue or what type of scanner might be needed to read these codes accurately.
This is a 1995 model with a 16-pin OBD-I connector, unofficially known as OBD-1.5. A standard OBD-II scanner won't work — you'll need a specialized scanner designed for GM's OBD-1.5 system. Search online for 'GM OBD-1.5 scanner' to find compatible tools. ABS codes may require a professional-grade scanner capable of accessing the ABS module directly. The red brake light typically indicates an issue with the basic hydraulic braking system — check brake fluid levels and ensure the parking brake is fully released. PS: Please turn off caps lock when posting — it's a common forum etiquette mistake.