Check ENCU Power Circuit
electrical
Description
There is a problem in the ENCU-44 terminal circuit, shorted when energized or open at other times, and the unit alarms only.
Activation Conditions
A problem has been detected in the ENCU-44 terminal circuit. If this alarm is activated while the circuit is energized, the circuit is detected shorted. If this alarm is activated at any other time, the circuit is detected open.
Unit Behavior
Alarm only.
Reset Conditions
Auto reset when the circuit is normal, or alarm may be manually reset using the display mounted keys or by turning the unit off, then back on again.
Corrective Actions
1. Check Wiring a. Inspect main microprocessor 3MM and ENCU connectors. Verify there is no damage to module, and no damage, moisture, or corrosion in connector. b. Use Component Test mode (Refer to Section 1.2.4) to energize the circuit. Must have minimum 11 VDC at 3MM-9. If no voltage at 3MM-9, download data and replace main microprocessor. Refer to Section 1.5. c. With circuit still in Component Test mode check voltage at ENCU-44. Must have minimum 11 VDC at ENCU-44. If no voltage at ENCU- 44, check connectors and wiring between terminals for damage, moisture or corrosion. d. Place the SROS in the OFF position and check continuity of the wiring from ENCU-19 to the “ENCUGND” connector extending from the battery negative cable connection. Check connectors and wiring between terminals for damage, moisture or corrosion. 2. Check ENCU: Replace ENCU with a known good component. Calibrate sensor and ENCU. Refer to Section 1.5.13