L WSHLD HEAT FAIL
(Caution)

L WINDSHIELD HEAT switch is set to ON and one of the conditions that follow occurs:

• L windshield heat subsystem for anti-icing cannot operate as usual because of a fault.
• L windshield and side window temperature controller (WTC) is not connected (P1 connector is off).

• L Windshield and Side Window Temperature Controller (WTC)
• L Windshield Heater
• L Windshield Temperature Sensor
• Associated Wiring

Advisory Wire/Service Bulletin:

• AW700-30-0463 - No Fault Found (NFF) initiative - Windshield Temperature Controller (WTC)
• Windshield Troubleshooting Report to help with windshield temperature controller NFF.

Forum Articles/Infoservice/Newsletter: None

NOTE: Before troubleshooting this CAS message, perform an interior and exterior inspection of the condition of the windshields. In support of this inspection, refer to the Windshield and side Window booklet.
NOTE: The left and the right windshield heat subsystems are not connected to each other but are symmetrical.
NOTE: When one of the failure message appears on the EICAS (R-L WSHLD HEAT FAIL, R-L WINDOW HEAT FAIL), if the CAIMS is active, the fault code from the unit will not be written in its memory.In order to do so, which would help the vendor in troubleshooting the unit, we have to switch the Windshield Temp Control System (WTC) to OFF on both sides, ensure the maintenance system (CAIMS) is inactive, switch the WTC back ON and wait that the message appears again so the information is written in the memory. Comply with the steps below:

1. Record the faulty label and bit in the CAIMS,
2. Exit the CAIMS and reset the Windshield Heat switch of the affected side (this is in order to write the Non Volatile Memory (NVM) in the unit.
3. Wait until the CAS message reappears

   1. If it reappears, write down the faulty label and bit on the MRA. (Material Return Authorization).
   2. If it does not reappear, the fault is considered as a nuisance.

NOTE: Verify C/B status on both pilot and copilot EMS CDUs. This CAS Message will post if both circuit breakers or Smart Contactor status is OUT or Tripped.

LOCATION	CB NO.	NAME
CCBP (A54)	CB-H10	L WSHLD HEAT 1
CCBP (A54)	CB-H11	L WSHLD HEAT 2
ACPC (A35)	SC-K15	AC 1 FEED

1. Check status of AC 1 FEED on EMS CDU, the AC 1 Feed being out or tripped can drive multiple CAS to post.
   BUS > AC 1 > AC 1 FEED.

   1. If AC 1 FEED CB is IN go to step 3.
   2. If AC 1 FEED CB is OUT, set to IN.

   AC 1 FEED

   CB	SYSTEM	PHASE	CAS
   CB-G6	ESS TRU 1	3	AC BUS 1 FAIL (Caution)
   CB-G3	EVS FAIRING HEAT	3	EVS HEAT FAIL (Caution)
   CB-G9	SLAT/FLAP PWR 1	3	SLAT-FLAP HALFSPD (Advisory)
   CB-H5	EVS WINDOW HEAT	1	EVS HEAT FAIL (Caution)
   CB-H6	A/T CTLR	1	A/T 1 FAIL (Advisory) A/T 2 FAIL (Advisory)
   CB-H7	PITOT 1 HT A	1	PITOT 1 HT FAIL (Caution)
   CB-H8	R ICE DETECTOR	1	ICE DETECTOR FAULT (Advisory)
   CB-H9	R AOA HEAT A	1	R AOA HEAT FAIL (Caution)
   CB-H10	L WSHLD HEAT 1	1	L WSHLD HEAT FAIL (Caution)
   CB-H11	L WSHLD HEAT 2	1	L WSHLD HEAT FAIL (Caution)
   CB-G12	TRU BAY FAN	3	ELEC SYS FAULT (Advisory)
   CB-B6	STAB TRIM CH1	3	STAB CH 1 FAIL (Advisory)

2. Did the CAIMS Fault & CAS messages clear after setting AC 1 FEED CB to IN.

   1. If YES, do close out.
   2. If NO, go to next step.

3. Select related CAIMS message below:
   Select an Item3040000IN - L WINDSHIELD TEMP CONTROLLER3040001IN - L WTC FAIL WSHLD CH W/O REGUL3040004IN - L WTC FAIL WSHLD CHANNEL3040010IN - L WSHLD SENSOR/WIRING [SHORT]3040016IN - L WSHLD HEATER OVERCURRENT3040017IN - L WSHLD HEATER/WIRING [OPEN]3040018IN - L WSHLD HEATER/WIRING [SHORT]3040019IN - L WSHLD SENSOR/WIRING [OPEN]3040020IN - L WSHLD TEMP CNTRL INPUT P0WER