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Home >> Isuzu >> 1988 >> Trooper II Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> I-TEC Control System >> Diagnosis & Testing >> Diagnostic Procedure (TCU)
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Diagnostic Procedure (TCU)

  1. The TCU will store up to 7 fault codes. These codes are displayed by an LED light in the cover of TCU.
  2. To access trouble codes, turn ignition on. Signal codes 2 and 6 (stored in memory) are displayed. Depress accelerator fully and let return. Signal code 6 is cleared. Start engine. Signal code 2 is cleared. Any trouble codes stored in TCU will not be displayed. See Fig 1 .
  3. To clear codes after repair. Repeat step 2).
Fig 1: Reading Diagnostic Codes
G94702
TCU TROUBLE CODE IDENTIFICATION

Code Problem Test
1 Faulty Knock Sensor Signal TCU CODE 1 
2 Interruption of Ignition Signal TCU CODE 2 
3 Short or Open Coolant Sensor TCU CODE 3 
4 Faulty Stepping Motor TCU CODE 4 
5 Shorted TPS TCU CODE 5 
6 No Signal From TPS TCU CODE 6 
7 Improper Voltage Supply TCU CODE 7