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DTC 4-4-1: Control Module Fault

  1. Control module is fitted with dual microprocessors. To compare results, microprocessors carry out all calculations in parallel. DTC sets when control module detects that calculations do not correspond with each other.
  2. Connect test box to control module. See Figure . Check control module by connecting an ohmmeter between control module housing and ground, then between test box terminal No. 1 and ground.
  3. If ohmmeter indicates continuity in both cases, ensure wheel sensor wiring is not too close to sources of interference (electric motors, phone connections, etc.). If wheel sensor wiring is okay, erase DTC and test drive vehicle. See TEST DRIVING VEHICLE  under DIAGNOSIS & TESTING. If DTC reoccurs, replace control module. If ohmmeter indicates an open circuit in both cases, replace control module.
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