If adapter is available, disconnect EGR position sensor connector and connect Adapter (49 G018 901 ) in harness. If adapter is not available, backprobe connector with voltmeter. See Fig 1 .

With EGR vacuum hose disconnected, connect vacuum pump. Turn ignition on and check voltages at connector. Use EGR POSITION SENSOR VOLTAGE table to compare results.

EGR POSITION SENSOR VOLTAGE

Terminal	Voltage
A	4.5-5.5
B	Less Than 1.5
C Without Vacuum	.25-.95
C With Vacuum	Approx. 4.0

If voltage is not correct at terminals A and B, check harness and connection at ECU connector terminals No. 2A and 2C. If voltage is not correct at terminal C, check sensor resistance, harness and ECU connector terminal No. 2F.
Check sensor resistance according to EGR POSITION SENSOR RESISTANCE table. If resistance is not within specifications, replace sensor.

Fig 1: EGR Position Sensor Connector Terminal Identification

Courtesy of MAZDA MOTORS CORP.

EGR POSITION SENSOR RESISTANCE

Terminals	Ohms
A-B	5000
A-C	700-5000
B-C	700-5000

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

EGR Position Sensor

Use the Manual With the Right Hardware

When to See a Mechanic

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