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Engine Running Test Mode Dodge Caravan I

3.0l v6 Mpfi System ~341 words

Engine Running Test Mode

  1. The engine running test mode is used to read the output signal of specific sensor to the SMEC when the engine is running. This test can be performed with the engine idling in Neutral with parking brake applied, or during vehicle road test. Engine running codes are 2-digit codes. The diagnostic read-out box MUST be used for this test; "CHECK ENGINE" light does not function in this mode.
  2. To enter this mode, connect diagnostic readout box to diagnostic connector. Ensure "READ/HOLD" button is in "READ" position. Start engine and observe diagnostic readout box display. When the O2 sensor is at operating temperature, the display will reveal if the system is switching rich-lean by alternately displaying "0" and "1" when in closed loop ("0" - Lean, "1"- Rich).
  3. When the engine is running in Neutral or Park and the O2 system switching is displayed, the idle motor system can be checked by moving the "READ/HOLD" button to the "HOLD" position. Engine speed should increase to about 1400 RPM.
  4. When the engine is running, O2 switching is displayed, and the "READ/HOLD" button is in "READ" position, depress and hold the "ATM" button until the desired engine running test code is displayed. Release "ATM" button. Move "READ/HOLD" button to the "HOLD" position. The SMEC will display the selected sensor output or will operate the engine in a specific mode for system diagnosis.
  5. Battery voltage, manifold vacuum and vehicle speed are actual readings and no correction is required. Coolant sensor and engine RPM readings are to be multiplied by 10 for actual readings. All other readings are to be divided by 10 for actual reading.

Note. If using a diagnostic read-out box other than Chrysler Diagnostic Read-Out Box (C-4805), follow manufacturer's instructions on how to connect diagnostic read-out box and obtain codes. Some diagnostic read-out boxes will display information that is not contained in this testing. This information may not be relative to diagnosing a problem. Only information contained in this article should be used during diagnosis.