The engine control module (ECM) determines engine misfire by detecting variations in crankshaft speed. Crankshaft speed variations can also occur when a vehicle is operating over a rough road. The wheel speed sensor produces an alternating current (AC) voltage that increases with wheel speed. The ECM receives a rough road signal from an electronic brake control module (EBCM), if equipped with the anti-lock brake system (ABS). The ABS can determine if the vehicle is on a rough road surface based on the signal from each wheel speed sensor. On vehicles with Non-ABS, a rough road signal is sent to an Analog/Digital (AD) Converter from a wheel speed sensor located at the left front wheel. The AD converter converts the analog signal to a digital signal, and sends the signal to the ECM. The ECM can determine if the vehicle is on a rough road surface based on the signal from the wheel speed sensor.

The ECM detects the difference between the vehicle speed and the magnetic wheel speed sensor is greater than 3 volts when the vehicle speed is greater than 0 km/h (0 mph).

OR

The ECM detects the wheel speed sensor is less than 0 volt, or greater than 4.98 volts when the vehicle speed is 0 km/h (0 mph).

DTC P2159 is a Type B DTC.

DTC P2159 is a Type B DTC.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

1. Engine idling, observe the scan tool DTC information parameter. DTC P2159 should not set.
2. If the vehicle passes the Circuit/System Verification test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

1. Ignition OFF, disconnect the harness connector at the analog/digital (AD) converter.
2. Test for less than 5 ohms of resistance between the ground circuit and ground.

⇒	If greater than the specified value, repair the ground circuit for an open/high resistance.

3. Ignition ON, test for battery voltage between the ignition voltage circuit and ground.

⇒	If less than the specified value, repair the ignition voltage circuit for a short to ground, or an open/high resistance.

4. Test for 4.8-5.2 volts between the signal circuit and ground.

⇒	If less than the specified range, test the signal circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the ECM.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.

5. Ignition OFF, test for 1-1.2K ohms between the wheel speed sensor circuit and ground.

⇒	If less than the specified range, test the wheel speed sensor circuit for a short to ground. If the circuit tests normal, test or replace the Wheel Speed Sensor.

⇒	If greater than the specified range, test the wheel speed sensor circuit, and ground circuit, for an open/high resistance. If the circuits test normal, test or replace the Wheel Speed Sensor.

6. If all circuits test normal, replace the analog/digital (AD) converter.

Important: This procedure is for vehicles without ABS. If the wheel speed sensor harness is damaged in any way, DO NOT repair the harness.

1. Ignition OFF, disconnect the harness connector of the wheel speed sensor.

Notice: Support the lower control arms in the normal horizontal position in order to avoid damage to the drive axles. Do not operate the vehicle in gear with the wheels hanging down at full travel.

2. Raise and support the drive wheels.
3. Engine idling, place the transmission into 2nd gear or drive for an automatic. Test for 70 mV AC between the wheel speed sensor signal circuit and ground circuit.

⇒	If less than the specified value, replace the wheel speed sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.