NOTE: For wiring diagrams, see WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. For vacuum diagrams, see VACUUM DIAGRAMS article in the ENGINE PERFORMANCE Section.

Turn ignition off. Remove ACG fuse in underdash fuse box for 10 seconds to reset ECU. Road test vehicle. With transmission in 2nd gear, accelerate to 4000 RPM and decelerate to 1500 RPM with throttle fully closed.
Verify if CHECK ENGINE light flashes Code 17. If light does not flash Code 17, problem is intermittent. Check for poor connections and loose wires at VSS connector on transaxle under right front of vehicle and terminals in connector C355 at right shock tower.
If CHECK ENGINE light flashes Code 17, block rear wheels, and set parking brake. Raise front of vehicle, and support with safety stands. Connect test harness between ECU and ECU connector. See Figure .
Turn ignition on. Slowly rotate left front wheel and measure voltage between ECU terminals C2 (positive) and A26 (negative). If voltage does not pulse between 0-5 volts, check for open or short in Yellow/Red wire between ECU terminal C2 (positive) and VSS. If wire is okay, replace VSS. If VSS is okay, substitute a known good ECU.
If voltage pulses between 0 and 5 volts, substitute a known good ECU, and recheck. If condition goes away, replace ECU.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Code 17: Vehicle Speed Sensor (VSS)

Use the Manual With the Right Hardware

When to See a Mechanic

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