Retrieving the Codes
Chrysler products provide engine diagnostic trouble codes by flashing the malfunction indicator lamp, or MIL. On earlier vehicles, this light may be the "Check Engine" light or the "Power Loss" light; regardless of the name on the light, they all have the same purpose: To indicate problems in the computer system, and to flash out diagnostic trouble codes.

Transaxles controlled by a dedicated computer can only have their diagnostic trouble codes checked through a scan tool, with a dedicated cartridge or software package. This procedure will only provide engine codes for systems with a separate transmission computer.

And the procedure for retrieving these codes is much easier than on other vehicles: Just turn the key on – off – on – off – on, within about two seconds. That’s all there is to it — the computer will begin flashing the malfunction indicator lamp to display any codes in memory. An 88 indicates the computer is ready to begin displaying codes.

Codes will appear as two sets of flashes, with a short pause between them. So code 23 appears like this:

There will be a short pause between the digits, and a longer pause between codes.

After displaying any codes in memory, the computer will flash out code 55, which indicates there are no further codes in memory.

Clearing the Codes
On most cars, once you’ve recorded any codes in memory, you’d erase the codes and take the car on a road test. But Chrysler systems only allow you to erase the codes two ways: The first — and by far the easiest — is with a scan tool. Just follow the directions on the scan tool display.

The only other way to erase the codes from memory is to cycle the key on and off, 51 times. These systems are designed to erase any codes from memory if the problem doesn’t show up again after 50 complete "key-on" cycles. So, if you turn the key on and off 51 times, any codes left in memory have to be hard codes; that is, they indicate problems that are there now — you should be able to find those problems by following the diagnostic procedure in your shop manual.

Any codes that don’t return would indicate one of two things: Either there’s an intermittent problem in the system, or they’re still in memory from an earlier diagnosis. Of course, turning the key on and off 51 times could be something of an annoyance. Once again, you’re better off with a scan tool.

Never disconnect the battery cable to clear the codes. Disconnecting the battery will clear all memories from the vehicle: radio presets, anti-theft codes, seat memories — all these and more will disappear if you disconnect the battery. And that’ll leave you with a whole series of headaches… and an unhappy customer.

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