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Test TC - Introduction

NOTE: You should perform this test when Codes 26, 47, 56, 66, 67, 91, 92, 93, 94, 97, 98 and 99 are displayed during KOEO SELF-TEST, Codes 26 and 65 are displayed during KOER SELF-TEST, or Codes 29, 49, 56, 59, 62, 66, 69 and 99 are displayed during CONTINUOUS MONITOR MODE testing or when directed here during DIAGNOSIS BY SYMPTOM tests. This circuit test is intended to diagnose only the following: harness circuits, CCC, CCS, 4WD LOW, EPC, CILY, OCS, SS1, SS2, SIGRTN, TOT, MLP, VPWR and ECA. The Transmission Solenoid Assembly (7G391) and Manual Lever Position (MLP) sensor (7F293) are not diagnosed in this circuit test as they are not controlled by the ECA.
Fig 1: RPM Sensor Circuit
G90H09315
Fig 2: 4WD Low & Overdrive Cancel Harness Schematic
G90D09323