'01 t&c: p0122, p0106 & p1496 5v supply

QuestionEdit

QUESTION: 2001 Town & Country LXi 3.3L Gas approx. 107000 miles

Current Symptoms: Engine will not idle, dies when shifted out of park Following Codes are set P1684: Battery Disconnected within last 50 starts P0122: Throttle Position Sensor Voltage Low P0106: Barometric Pressure Out of Range P1496: 5 Volt Supply Outlet Too Low

Approx. 5 weeks ago after approx 80 min highway drive followed by 5 min surface street driving with outside air temp in high 90's lost power momentarily accelerating from a a stop light. Was able to restart, continue trip and bring to mechanic next day using starting fluid. Mechanic diagnosed faulty fuel pump and replaced. Next day had P0455 Evap Leak Monitor Large Leak Detected (Mechanic had pinched the pump gasket).

Approx ten days later had P0601 Internal Controller Failure and P0700 EATX Controller DTC present and transmission went into LIMP mode. Mechanic diagnosed TCM failure after checking the TCM for codes and replaced TCM.

Driving home on 8/7 ABS light came on.

Parked at airport from 8/11 - 8/18. Returned to a dead battery. Jump started, drove home, placed battery on charger overnight. O'Reilly Super Start from Nov 2009. O'Reilly test equipment said bad battery they replaced under warranty.

ABS light was off after jump start

Current problem first occurred on Sunday. Wife drove approx. 20 miles with outside air temp in high 90's Made several low speed turns. ABS/Brake light came on followed by Check Engine Light and a loss of useful power. When AAA wrecker arrived was able to start and drive out of garage. Had it towed to my mechanic (upgraded to AAA Plus after fuel pump incident :) )

P1684, P0122, P0106 and P1496 were set, but engine appeared to be running well. Mechanic checked Throttle Position Sensor and Manifold Pressure Sensor and they appeared to be okay. Mechanic ran engine for 4+ hours and used minivan to run errands over two day period without a repeat occurrence.

I picked it up drove about 3 miles, stopped for about 20 minutes and then drove home on highway (approx 45 minutes)(again with outside air temperature in high 90's). About a half hour after I got home my wife went to drive it and problem recurred.

Did the On-Off key dance and instrument cluster displayed above codes. Disconnected the battery then disconnected the MAP sensor and checked harness. Terminal 1 showed 0.8 ohms. Cleaned secondary battery connections, reconnected the battery and checked MAP Sensor Terminal 1 & 2. This showed 4 volts with ignition on. Did not back probe terminals 2 & 3 or check the Throttle Position Sensor (it was too dark and getting late)

As of 1030 last night problem has not self resolved (as it did on Sunday)

Mechanic suspects harness or 5 volt regulator.

Here's the question:

Short of swapping parts how can I tell if it's the harness or the 5 volt regulator (on the PCM).

I've got a schematic (generic for '96 to '02) in Chilton's but do not have a pin map for the PCM. It appears that the 5 Volt Supply also feeds the A/C Pressure Transducer which only requires .098 volts and does not appear to have a P code

Thanks

ANSWER: Let me look at the wiring diagrams and get right back with an answer. Thanks for the detailed history of the situation.

---------- FOLLOW-UP ----------

QUESTION: Looking through your answers to similar questions on other vehicles it looks like I need to know where the splice for the 5V supply line is. Should I start a new thread requesting that image with my e-mail or postal address and mark it private?

AnswerEdit

Hi Seth, The splice is located at the right rear corner of the engine in a fat harness that comes from the pcm and passes by the front manifold's exhaust pipe (maybe melted insulation?) and then passes near to the coil pack. The splice itself is located just above the exhaust pipe. I hope this is sufficient description but you can let me know as there is a drawing that show splice 116 location. Please rate my answer, thanks. Roland