Just Found several copmputer fault codes on my 93 Dodge/Cummins 12v 3/4 ton Auto trans. Does anybody know of a site or knows the codes so I can fix the problem. I will post the code numbers later tonight. There is more then one and im having problems with my OD shiting out of gear at highway speeds and not always shifting in od. got the kicked down cable unhooked and waiting for the dealer to get in the new cable. Also does any one know how to clear the codes with out the visit to the dealer.

 

The 93 uses the early OBD codes, and they can be cleared from memory by simply disconnecting the negative battery terminals for at least ten seconds.

There are only a handful of codes used by the ODB systems on the Diesels back in 93, and even of those listed only a few actually will ever display, the rest may if you were struck by lightning, so I listed them too.

11- No crank reference signal during cranking - no big deal on the 93.
12- No codes, battery connection problem - no juice = no light, so I never seen this code.
15- No vehicle speed sensor - speedometer and cruise will not work either.
23- Intake air temperature sensor voltage high or low (no sensor until 98.5, but a code - go figure).
24- TPS voltage high or low.
33- AC clutch relay circuit open or shorted - AC does not work either.
34- Open or short in speed control vacuum or vent door circuits - cruise control and defrosters will not work either.
37- Torque converter solenoid circuit open or shorted. Highly likely on an automatic. OR,
37- Transmission temperature sensor voltage above or below accepted values - never seen this on a 93 as they still use a mechanical governor and do not check transmission temp.
41- Problem with charging circuit - The batteries will also be dead or the headlights very dim and no charging. Never seen this code, but I suppose it exists.
42- Auto shutdown relay shorted or open.
44- Battery temperature sensor malfunction. If 44, 46 or 47 appear, do a search on the forum for the use of an external voltage regulator and bypass the ECM based charge control system. There are several threads on how to do this, complete with photos and part numbers. The second gen and first gen use the same integrated charging system, so look in the 12 valve section.
45- Transmission overdrive solenoid malfunction - real common problem.
46- Charging system voltage too high.
47- Charging system voltage too low.
53- Internal PCM failure - the PCM is an ECM in 93 and does not do much, but it will be likely you will have cruise control, charging, and instrument problems if this is present.
55- Check engine lamp fault - actually an end of message code, just ignore it.
63- Computer failure.
68- PCM not active. Actually an ECM, but if either 63 or 68 are present and everything with the engine and charging system still works, ignore it on a 93.