Sensor Input Voltage Low INP1
electrical
Description
Voltage from the main microprocessor to the components is less than 4.5 VDC, and the unit gives alarm only.
Activation Conditions
Voltage from main microprocessor to the components is less than 4.5 VDC
Unit Behavior
Alarm only.
Reset Conditions
Auto reset when voltage is correct, alarm reset or alarm may be manually reset by turning the unit off, then back on again.
Corrective Actions
1. Check System Pressures: Install manifold gauge set and check and compare compressor discharge, evaporator outlet and suction pressures with those shown in Unit Data. Refer to Section 1.9.12 for instruction on comparison. 2. Check Wiring: If a transducer reading is not within a reasonable range of gauge reading, check wires to sensors for short. For CSP, check wiring from 2MM-20, 2MM-30 and 2MM-9. For EVOP, check wiring from 2MM-25, SP-20 and 2MM-17. For CDP, check wiring from 2MM-21, SP-20 and 2MM-10. For ECOP, check wiring from 2MM-28, SP- 20 and 2MM-14. 3. Check CT Wiring: Check wires to sensor for short. Check wiring from 2MM-29, 2MM-12 and 2MM-23 to PCM. 4. Replace Main Microprocessor: Download data and replace main microprocessor. For complete Main Microprocessor Module replacement instructions refer to Section 1.5.2.