Chrysler Full-Size Vans 1989-1998 Repair Guide

Reading Codes


See Figures 1 and 2

There are two kinds of codes stored in the ECM: hard faults and continuous faults. A hard fault is a fault detected that is malfunctioning at the time of testing. A continuos fault is a fault that was detected by the ECM, but is not malfunctioning at the moment. The ECM will erase this code if the fault does not recur within a set amount of time; different year models take different amounts of time to clear these code, however it usually is around 50 starts.

When the MIL lamp (Check Engine light) illuminates while the engine is running, it indicates a detected fault by the ECM. To retrieve this information from the ECM you can use two methods. The first is to use the DRB-II scan tool, or equivalent, and retrieve the codes. The second way to retrieve the codes is to cycle the ignition switch as follows: ON - OFF - ON - OFF - ON within five seconds. The MIL lamp will then flash the DTC(s). Each code, if there is more than one, will be preceded by a four-second pause to distinguish it from the previous code. An example of a DTC flashed by the MIL would be:

  1. Lamp on for two seconds, then turns off.
  3. Lamp flashes two times, then pauses, then flashes seven times.
  5. Lamp pauses for four seconds.
  7. Lamp flashes three times, then pauses, then flashes one time.
  9. Lamp pauses for four seconds.
  11. Lamp flashes five times, then pauses, then flashes five times.

In this ECM, the DTC's stored were 27, and 31. The ECM will then flash code 55 after it has reached the last code stored in its memory.

The second method of DTC retrieval will not work on 1996-98 OBD-II vehicles. OBD-II DTC's must be retrieved using the DRB-II scan tool or equivalent.

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Fig. Fig. 1: Although sometimes no DTC's are found, that does not rule out a potential problem

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Fig. Fig. 2: When you find a DTC, proceed to diagnostics