Check the modulator valve inlet and outlet circuit resistance. Check circuit 376T+ for intermittent short to ground. To make sure of the integrity of the wire or circuit, a load test is necessary. Check the modulator valve inlet and outlet circuit resistance. The following procedures for servicing brakes are recommended to reduce exposure to non-asbestos fiber dust, a cancer and lung disease hazard.
To adjust the sensor, push the sensor in until it contacts the tooth wheel. Resistance below 50 or above 200 ohms Check the relay coil, relay coil ground circuit, and Circuit 376H for an open circuit. Resistance reading not close to zero Check the modulator ground circuit, repair as necessary. With the modulator valve connector removed, measure the resistance across Pins 10 and 8 on the modulator connector. Action 3 Troubleshooting and Testing Figure 3. Failure to do so may cause reduced braking force and result in serious personal injury. This fault usually occurs when there is excessive tire spin for more than 16 seconds.
Ground is open or has high resistance Repair ground circuit as necessary. Braking force from the Hydraulic Power Brake may be reduced or impaired. Measure the resistance between pin 1 of the X3 green connector and a good chassis ground. Voltage Checks Check all the power wire circuits, with the key off, disconnect the 2-pin and 31-pin connectors. Do not shake or use compressed air to remove dust from work clothes. The problem may be intermittent. Circuit 378T- is shorted to power.
Action 3 Troubleshooting and Testing Figure 3. Incorrect tire size or size variation exceeds 16 percent Install the correct size tires. Disconnect the connector from the valve and perform the modulator valve resistance test. Accordingly, workers must use caution to avoid creating and breathing dust when servicing brakes. A pull-down menu will appear. Voltage is less than 0.
No voltage at pin 6. There should be no voltage key off. Repeat the test between pin 4 and ground. Description and change wrong tire. An open circuit or short to ground has been detected.
Select Close to exit this screen. This eliminates the concern of the polarity of the meter leads during voltage measurements. Resistance reading close to zero Go to Test 4. Disconnect the sensor at the sensor connector. The problem may be intermittent. Voltage is less than 9.
The easiest way to identify is by locating the unit metal tag, with the part listed pictured. Disconnect the sensor connector from the chassis harness. Resistance in both circuits is not within 4 to 8 ohms. Miscellaneous Outputs Engine Data Link Select Engine Data Link to display the Data Link test screen. Resistance reading below 500 or above 2000 ohms Replace the wheel sensor. Check the modulator valve inlet and outlet circuit resistance. If fault continues to appear, check the wiring in the X2 black connector.
Repeat between pin 11 and ground. Action 3 Troubleshooting and Testing Figure 3. Select Close to exit this screen. Resistance reading below 500 or above 2000 ohms Replace the wheel sensor. The solution should be applied with low pressure to prevent dust from becoming airborne.
Measure the resistance between the pins on the sensor connector. Silicosis gradually reduces lung capacity and efficiency and can result in serious breathing difficulty. Driving the vehicle with active faults present can result in an accident and serious personal injury. Check air gap and push sensor back in afterward. Measure the resistance at the sensor connector on the sensor side.
Wheel speed signal drops out periodically at speeds higher than 10 kph. Make sure brake chatter is not causing the problem. During normal operation, the gap should not be greater than 0. This fault usually occurs when there is excessive tire spin for more than 16 seconds. Use a solution containing water, and, if available, a biodegradable, non-phosphate, water-based detergent. The gap should not be greater than 0.