Throttle Position Sensor: Adjustments

NOTE: Use a precision voltmeter with a scale of 0.01 volts to inspect or adjust throttle sensor.

1. Remove air hose from throttle body.
2. Disconnect throttle sensor connector (3-pin).

Throttle Sensor Test Harness:

3. Connect adapter (Mazda SST #49 G018 901) between throttle sensor and wiring harness.
4. Turn ignition switch "ON."
5. Make sure throttle valve is fully closed.

Throttle Sensor Voltage Testing:

6. Measure BLACK and RED wire voltages. BLACK should be approx. 0V and RED should be 4.5-5.5V.
7. If not as specified, check battery voltage and wiring harness. If these are OK, replace the ECU.
8. Record RED wire voltage.

Throttle Sensor Voltage Testing:

9. Check that voltage at BLUE wire corresponds with RED voltage received in step 6 by using this chart:

RED VOLTS BLUE VOLTS

4.50-4.59 0.37-0.54
4.60-4.69 0.38-0.55
4.70-4.79 0.39-0.56
4.80-4.89 0.40-0.57
4.90-4.99 0.40-0.58
5.00-5.09 0.41-0.60
5.10-5.19 0.42-0.61
5.20-5.29 0.43-0.62
5.30-5.39 0.44-0.63
5.40-5.49 0.44-0.64
5.50 0.44-0.66

Throttle Sensor Adjustment:

10. If not as specified, loosen throttle sensor mounting screws and adjust BLUE wire voltage by rotating throttle sensor. After adjusting voltage, tighten throttle sensor mounting screws and recheck voltage.

Throttle Valve Fully Open:

11. Hold or prop throttle valve fully open.
12. Check BLUE and RED wire voltages. Check that BLUE voltage corresponds with RED voltage listed in this chart:

RED VOLTS BLUE VOLTS

4.50-4.59 3.58-4.23
4.60-4.69 3.66-4.32
4.70-4.79 3.74-4.41
4.80-4.89 3.82-4.51
4.90-4.99 3.90-4.60
5.00-5.09 3.97-4.70
5.10-5.19 4.05-4.79
5.20-5.29 4.13-4.88
5.30-5.39 4.21-4.98
5.40-5.49 4.29-5.07
5.50 4.29-5.17

13. If not as specified, replace throttle sensor.
14. Turn ignition switch "OFF."
15. Disconnect test adapter and reconnect sensor connector.
16. Disconnect negative battery terminal and depress brake pedal for at least 5 seconds to eliminate ECU malfunction memory created during inspection.