Chrysler Repair: Multiple fault codes: engine sensors, throttle position sensor, volt power supply

Question
My van is acting up not sure what codes to have the repair people look at first P0206 Cyclinder 6 Injector, P0108 MAP Sensor / Baro High inpact, P0118 Coolent Temp High sensor, P0122 low impact Throttle postion sensor, P0420 Catalyst sytem efficiency below threshold # 1, P1478 02 Sensor, P0123 Code - Throttle Position Sensor/Switch A Circuit High Input, And the other code I am not sure what it is the code was P1496.  I am not sure how much some of these sensors are or once we get one or two of these fixed will the others clear out?

Answer
Hi Brandi,
I believe that the sensor codes are likely inter-related as having all set codes at once, independently, is unrealistic. Most likely there is a wire, either a ground wire or a voltage supply to the sensors wire, that is shorting to ground, shorting to the wrong voltage, or open, or the ground wire is open. A competent tune-up person should be able to find the reason and fix all without changing the sensors (unless a specific sensor remains a problem after the other codes have 'cleared'). So codes 108,118, 122 and 123 (which are contradictory), and 1496 would all be resolved with that sort of troubleshooting effort and thus avoid unnecessary replacement of parts and labor. It appears that the 5 volt power supply wiring or the sensor ground is the one that is involved. So try to find the sharpest tune-up mechanic who has access to the Chrysler wiring diagrams and ask him/her to try that approach to all of those.
The 206 could either be the injector on cylinder 6 or the wire that activates it, so again look at the wire first, then consider changing the #6 injector.
The 1478 is minimal having to do with the temp sensor in the cabin. That can be set aside for later. The catalytic converter might well be resolved once you get the sensor and #6 issue solved and you drive it for a while with the engine running right.
That is my opinion. Don't authorize a 'fishing trip'/throwing parts at it" approach to do everything piecemeal which could cost many hundreds of dollars.  Start with the injector #6 and a search for a simple 'common cause' wiring solution for all those sensor codes.
Please let me know how it works out.
Roland
PS Please 'rate' my answer and where you see the question about 'volunteer of the month please consider a 'yes' in response. Thanks.

PPS Thanks for the rating and your kind remarks. I might mention another possibility is that one of the sensors may be causing a short due to an internal failure, so that is another thing that a competent tune-up person would look for as well. It is not rocket science here, just smart use of a volt-ohm meter. Removing the plug from each sensor, one at a time would reveal if that were the case.

PPPS: The three sensors that show codes all share a common "ground" wire to pin 43 of the engine computer that is dark green/dark blue in color, so that is a specific suspect in my mind. In addition, 2 of the 3 sensors use a 5V power wire, and the 1496 raises a suspicion that the 5V supply is shorted to ground. So that all leads me to believe that it either the ground wire, or the pink/yellow 5V wire on pin 61 that is compromised, or one of the the 3 sensors (MAP, TPS, AC Pressure) that use the 5V supply is shorted to ground. Show this to whoever is working on the problem.


Brandi's follow-up report:
Ok I found a friend who had a auto shop and he hooked the van up to the machine and got the same codes as we did before. In the process of starting with the Fuel Injector # 6 he noticed that the Harness wiring when touched had made the van die out after looking at the harness wiring it was fried almost to the point that the van could have caught on fire. I am very thankful for your in site knowledge. We replaced the harness wiring and a tune up and my van has never ran better.

Hi Brandi,
Thanks for confirming my suspicion of some sort of wiring short circuit as the reason for the multiple codes. I am pleased to learn that the engine is now running well. I am revising my last answer to you so as to complete the story and show how the problem was resolved.
Roland