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Problem Symptoms Table

The suspected circuits or parts for each problem symptom are shown in the table below . Use this table to troubleshoot when, during a DTC check, a "Normal" code is displayed but the problem is still occurring. Numbers in the table show the inspection order in which the circuits or parts should be checked.

HINT:

In some cases, the problem is not detected by the diagnostic system even though a problem symptom is present. It is possible that the problem is occurring outside the detection range of the diagnostic system, or that the problem is occurring in a completely different system. SeePROBLEM SYMPTOMS TABLE on in the Cruise Control System - Diagnosis as in an example.

PROBLEM SYMPTOMS TABLE - CRUISE CONTROL SYSTEM

Symptom Suspect Area
Main switch cannot be turned ON.
(Indicator light on the combination meter does not come on.)
  1. Cruise control switch circuit
  2. CRUISE MAIN indicator light circuit
  3. ECM
Speed setting cannot be done. (Indicator light on the combination meter comes on when the main switch is turned ON, but goes off when operating 'SET' function.)
  1. Cruise control switch circuit
  2. ECM
Speed setting cannot be done. (Indicator light on the combination meter comes on when the main switch is turned ON and it remains ON, while operating 'SET' function.)
  1. Cruise control switch circuit
  2. Stop lamp switch circuit
  3. PNP switch circuit
  4. Combination meter system
  5. ECM
While cruise control driving, the set speed is canceled. (Indicator light remains ON.)
  1. Cruise control switch circuit
  2. Vehicle speed sensor circuit
  3. Stop lamp switch circuit
  4. CRUISE MAIN indicator light circuit
  5. PNP switch circuit
  6. ECM
Hunting occurs. (Speed is not constant.)
  1. Vehicle speed sensor circuit
  2. ECM
Speed setting cannot be canceled. ('CANCEL' function failure ONLY)
  1. Cruise control switch circuit
  2. ECM
DTC is not output, or is output when should not be.
  1. DLC3 circuit
  2. ECM
CRUISE MAIN indicator light does not come on.
  1. Cruise control switch circuit
  2. CRUISE MAIN indicator light circuit
  3. ECM
  4. Combination meter assy