2001 Dodge Grand Caravan 3.3L P1338 Auto Shut Down

187,00kms on, transmission went into to default mode, only had 2nd and reverse. Took it to garage, mechanic said the tranny control module (tcm) was bad, replaced it and van was good for a day. Slipped back into default mode. My neighbour (same mechanic) suggested we trace all the wires down. Pulled tcm, ipm, and computer, traced all wires could not find a problem. The tranny oil was changed about 8 months ago and when the tcm was changed. Anyway, put it all back together and no start, Code is P1388 Automatic shutdown relay control circuit. Can someone explain to me what this circuit is for and easiest way to test? Can I bypass it to start?

One of the circuits feeding the ASD relay in the fuse box under the hood is likley open! It may even be the fuse box itself, they corrode internally alot. The wiring gets damaged alot when the transmission is removed and the failure you had with the transmission module may have been improperly diagnosed, when the ASD circuits don't work correctly the transmission can go into limp. Im not sure how you are checking the ciruits if just visual then not quite the best way. Was the tranmission module, new, used? are you sure you sourced the correct one? how are you pulling these codes? will the tcm communicate with a scan tool?

The fuse block was replaced last october, with a brand new one from the dealer. The tranny was never removed. The wires were first checked visually, by removing the tape/coverings and looking for corrosion/nicks /etc. none found. The using alldata schematic diagrams wires were checked for continuity from, IPM (intellegent power module) to TCM (tranny module), from IPM to solenoid/pressure switch assy, to TCM, also did continuity check on transmission safety shutdown relay. The TCM that was just put in came new from the dealer. The first codes were picked up using a scan tool (Idon't know which type) at the garage. (This not being able to start only came to light after we put all the connectors back together, and they are in the right locations.) The two codes I picked up today were from the odometer. One P1684 (battery disconnected last 50 starts) and the P1388 for the autoshut down relay. I believe that I should concentrate my efforts on the auto shutdown circuits. Problem here is I do NOT have the schematics for these circuits, any help out there? THANKS IN ADVANCE.

It happened since which connector? The ones at the fuse box or at the tcm?
It still sounds like a poor or loose connection right there if happened right after, I've seen the wiring rott about 18 inches up from the tcm connector and the wiring harness around the frt of the transmission gets bad alot, try wiggling it and see if you can get the van to start? Have you checked all the fuses, I know it sounds stupid but It's a good first step. so you need the schematic for the ASD relay?

Van was starting well before. After I took off the IPM and TCM, input/output speed sensors, and the 2 on the computer and put them back, is when it would not start. Checked all the fuses, OK, also checked the ASD relay coil good contacts operating properly, i.e n/c closed and n/o open, also energized it and tested contacts, OK. I will check the wiring in the areas you suggested, because I did wiggle them around alot looking for a bad connection. I may have just made a bad one worse. May have to wait till tommorow night for a scanner, but using an ohmmeter I'm tracing the ones I can see on the schematics I have. I don't know the connector #'s on the PCM for the ASD circuits, thats the schematic I meant. i believe the original code was P1768.

Thanks A Lot AGAIN
ADET

VAN STARTED I HAD TWO CONNECTORS SWITCHED IN THE BACK OF THE IPM (FUSE BLOCK). STILL HAVE TRANSMISSION IN LIMP MODE. I THINK THE SCHEMATICS FOR THE TRANSMISSION SAFETY SHUTDOWN RELAY ARE INCORRECT. LOOKING AT IT, THE DIAGRAM INDICATE THAT #30 ON THE RELAY SHOULD HAVE CONSTANT 12V POS. FROM FUSE 15 AND BATTERY A1, AND CONTACT 87 SHOULD HAVE 0 VOLTS. MY RELAY IS THE OPPOSITE. AND I STILL HAVE POS 12 VOLTS TO THE SOLENOID PRESSURE SW ASSY AT PIN 4, BUT THE SOLENOIDS ARE NOT CHATTERING/WORKING. WILL PUT A SCANNER ON TOMMOROW AND ENEGIZE THE SOLENOIDS. THANKS