Check Solenoid Pull Circuit
electrical
Description
The Solenoid Pull circuit feedback is out of range; the unit gives an alarm only.
Activation Conditions
Trigger On Solenoid Pull FET is ON and FET Feedback Voltage is below Minimum ON Threshold OR Solenoid Pull FET is OFF and FET Feedback Voltage is above Maximum OFF Threshold. Trigger Off If alarm was active when Solenoid Pull was ON, trigger OFF if Output is ON and FET Feedback Voltage is sensed in Active range OR If alarm was active when Solenoid Pull was OFF, trigger OFF if Output is OFF and FET Feedback Voltage is sensed in Inactive range OR Alarm Reset OR Cycle Power
Unit Behavior
Alarm only
Reset Conditions
See manual.
Corrective Actions
1. Verify if condition occurs when solenoid pull output is ON or OFF a. Check solenoid pull output status in System Values menu in Cabin Tech. b. If status is ON go to step 2. c. If status in OFF go to step 6. 2. Inspect Harness a. Inspect APU harness and connections between APU J2-6 and fuel solenoid. Connections must be free of corrosion, moisture, and terminal connections secure 3. Check harness continuity between APU J2-6 and FS-B – must be less than 1.0 Ω 4. Check fuel solenoid for open circuit. Measure resistance between FS-B and FS-C 5. Replace APU module. 6. Remove APU J2-6 terminal from connector and reinstall connector into module. a. Check for voltage between J2-6 and starter ground. b. If voltage is present, check APU harness for short to power between APU module and fuel solenoid. c. If voltage is not present, replace the APU module.