We didn't properly rewire a sensor MAF sensor and damage the PCM.

I want to replace the PCM but how can we do this with the anti theft system?

Can I buy a used PCM and ignition from same vehicle?

Any help or guidance?

Can the original PCM be repaired?

Thanks.

 

Depending on what was damaged and checked out it would be difficult to say if the damage could be repaired.
If you are certain the PCM has been damaged,,,, a replacement PCM would need to be programmed to the specs of your particular vehicle. This would require a capable scan tool and the equipment to program the replacement PCM to your vehicle. This could be done either by a shop with the knowledge and equip , a dealership, or a capable locksmith with the right equipment.
Would we be asking too much if we asked what exactly was done incorrectly and how you determined the PCM was damaged? Some vehicles will run without the MAF plugged in since the PCM will revert to a fixed setting.

 

1. A rodent ate the wires leading to the ignition coil. I replaced them. Car returned to normal.

2. A rodent then ate the wires leading to the MAF sensor. My son couldn't rewire the connector due to damage so we purchased another sensor connector and sensor. He reversed the wires on installation. We replaced the MAF sensor and wired the connector correctly but now we get no updating of the MAF or IAT readings on the the scan tool. The car has a hard start, rough idling and the code error code for the IAT and MAF.

 

Have you tried to disconnect the negative battery cable and hold it on to the positive cable end for 10-15 minutes. This should allow some of the PCM memory to go away and might remove a problem. Do you know exactly what wires were switched? One of them should have been a vehicle 5 volt reference wire, one the signal to the PCM and the other a ground. There are also Intake air temp wires with that plug and sensor.
Did you check if the mixup blew any fuses , could have ?

 

OP

try as suggested by resetting your PCM by disconnecting the ground at battery and connect it in some way to the + cable. A wire with clip ends will work if you don't want to hold it for 10 minutes. The capacitors in PCM need to completely discharge which takes about 10 min

If you did kill the PCM with the wiring mishap than yeah you need a new PCM. Dealership would need to re-flash it with your VIN and key ID along with the program for your car

I believe locksmith have ability to burn a new key to a PCM but not program the PCM itself

 

A shop with a capable scan tool and knowledge should be able to handle the new PCM steps required to set it up. There are mobile units that some shops use that can also do this.