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Test NTC-26A: Checking A/C System

NOTE: Perform TEST NTC-1A: NO TROUBLE CODES (NTC) TESTS  before proceeding.
NOTE: Verify A/C system is properly charged before performing procedure.
  1. Using scan tool, actuate A/C clutch relay. If A/C clutch relay did not engage, go to next step. If A/C clutch relay engaged, A/C clutch is okay. Test is complete. Perform TEST VER-2A: ROAD TEST VERIFICATION .
  2. Turn ignition off. Remove A/C clutch relay. Using a 12-volt test light, check fused B+ circuit at A/C clutch relay connector. See A/C CLUTCH RELAY CONNECTOR WIRE IDENTIFICATION  table. If test light is brightly illuminated, go to next step. If test light is not brightly illuminated, repair open fused B+ circuit. Perform TEST VER-2A: ROAD TEST VERIFICATION .
  3. Using a jumper wire, connect fused B+ circuit to A/C clutch relay output circuit at A/C clutch relay connector. See A/C CLUTCH RELAY CONNECTOR WIRE IDENTIFICATION  table. If A/C clutch did not engage, go to next step. If A/C clutch engaged, replace A/C clutch relay. Perform TEST VER-2A: ROAD TEST VERIFICATION .
  4. Disconnect A/C clutch 2-pin connector. Using a 12-volt test light, check voltage on A/C clutch relay output circuit at A/C clutch connector. See A/C CLUTCH CONNECTOR WIRE IDENTIFICATION  table. If test light is brightly illuminated, go to next step. If test light is not brightly illuminated, repair open A/C clutch relay output circuit. Perform TEST VER-2A: ROAD TEST VERIFICATION .
  5. Using a DVOM, check resistance of ground circuit between A/C clutch 2-pin connector and ground. See A/C CLUTCH CONNECTOR WIRE IDENTIFICATION  table. If resistance is less than 5 ohms, replace A/C clutch coil. Perform TEST VER-2A: ROAD TEST VERIFICATION . If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-2A: ROAD TEST VERIFICATION .
A/C CLUTCH RELAY CONNECTOR WIRE IDENTIFICATION

Application Wire Color
Terminal A
Fused Ignition Switch Output Circuit Light Green/Black
Terminal B
Fused B+ Circuit Red/Brown
Terminal C
A/C Clutch Relay Control Circuit Dark Blue/Orange
Terminal D
A/C Clutch Relay Output Circuit Dark Blue/Black
A/C CLUTCH CONNECTOR WIRE IDENTIFICATION

Application Wire Color
A/C Clutch Relay Output Circuit Dark Blue/Black
Ground Circuit Black