Diagnostic Trouble Codes

WARNING: This page is about a different car, the 2004 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostic trouble codes (DTCs) are codes stored by the Powertrain Control Module (PCM) that help us diagnose Powertrain, Transmission problems. The Electronic Transfer Case Diagnostic trouble codes (DTCs) are stored in the Transfer Case Control Module. They are viewed using the DRBIII® scan tool. Some engine driveability problems can be misinterpreted as a transmission problem. Ensure that the engine is running properly and that no engine DTCs are present that could cause a transmission complaint.

If there is a communication bus problem, trouble codes will not be accessible until the problem is fixed. The DRBIII® will display an appropriate message. The following is a possible list of causes for a bus problem:

open or short to ground/battery in PCI bus circuit.
internal failure of any module or component on the bus

Each diagnostic trouble code is diagnosed by following a specific testing sequence. The diagnostic test procedures contain step-by-step instructions for determining the cause of a transmission diagnostic trouble code. Possible sources of the code are checked and eliminated one by one. It is not necessary to perform all of the tests in this article to diagnose an individual code. These tests are based on the problem being present at the time that the test is run.

If the Engine or Transmission records a DTC that will adversely affect vehicle emissions, it will request (via the communication bus) that the PCM illuminate the Malfunction Indicator Lamp (MIL). Although these DTCs will be stored in the PCM immediately as a 1 trip failure, it may take up to five minutes of accumulated trouble confirmation to set the DTC and illuminate the MIL. Three consecutive successful OBDII/EURO III trips or clearing the DTCs with a diagnostic tool (DRBIII® or equivalent) is required to extinguish the MIL. When the Transmission requests that the PCM illuminate the MIL, the PCM sets a DTC P0700 ($89) to alert the technician that there are DTCs in the Transmission. The PCM DTC ($89) must also be erased in the PCM in order to extinguish the MIL.