Sensor Failure

1. Connect the 60 Pin Breakout Box to the Electro-Hydraulic Control Unit (EHCU) with the ABS Adapter Cable.
2. Disconnect the suspect anti-lock brake sensor.
3. Check the harness for short to ground.
a. Monitor the resistance between 60 Pin Breakout Box pins and ground:





NOTE: Use 88 Digital Multimeter with the minimum resistance hold feature enabled for this test.

b. Drive over rough roads at various speeds.
c. If there is continuity between either circuit and ground, repair the circuit for a short to ground.

4. Check the harness for an open circuit.
a. Connect a jumper between the two pins on the suspect sensor connector.

NOTE: Connect the jumper securely to the suspect sensor connector.

b. Monitor the resistance between the ECC IV 60 Pin Breakout Box pins:





NOTE: Use 88 Digital Multimeter with the maximum resistance hold feature enabled for this test.

c. Drive over rough roads at various speeds.
d. If there is open circuit detected between pins, repair the circuit(s) for an open circuit.
5. Check suspect sensor pigtail.
a. Monitor the resistance between suspect sensor terminals while wiggling the pigtail. Front sensor maximum resistance is 500 ohms, rear sensor minimum resistance is 1,500 ohms.

NOTE: Use 88 Digital Multimeter with the maximum resistance hold feature enabled for this test.

b. Monitor the resistance between suspect sensor terminals while wiggling the pigtail. Front sensor minimum resistance is 300 ohms, rear sensor minimum resistance is 900 ohms.
c. If the resistance does not remain within specification, replace the sensor.
d. Monitor the resistance between a sensor terminal and ground on the highest resistance scale of the meter, while wiggling the pigtail.

NOTE: Use 88 Digital Multimeter with the minimum resistance hold feature enabled for this test.

e. If the meter shows anything but open circuit, replace the sensor.