When replacing the ecu, do I have to have it programmed upon installation?

I am replacing the ecu on a 99 Durango because of an error code diagnosis and I am wanting to know if the ecu must be programmed upon installation

My car has 16100 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
The PCM will need to be programmed if you have theft system that is factory installed. The PCM will need to be programmed to communicate with the theft module.

How to Identify and Fix Common car Problems ?

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The PCM, or powertrain control module, is your vehicle`s onboard computer. PCM Reprogramming or reflashing is essentially a software upgrade and may be required to resolve a hot or cold starting issue, idle roughness, stalling, or an emissions failure.
Not to mention, if you go the route of replacing your faulty PCM, you`re able to save cost on labor by simply replacing it yourself. All you have to do is make sure you identify the correct PCM for your particular vehicle—because there are a lot of different types and you want to avoid unnecessary returns.
PCMs are built with microchips that can be reprogrammed electronically without being removed from the vehicle. Reflashing is a process where you electronically transfer approved files from a vehicle manufacturer`s website using a diagnostic connector. This process has many names.
A faulty ECM can send poor data to your vehicle`s transmission control module (TCM). As a result, the vehicle cannot properly shift gears or apply power, causing the shift to feel awkward, delayed, or even jarring. When this occurs, the engine may sporadically become more active or stall out.
Principal Care Management (PCM) Services – CPT codes in 2022: 99426—99427. CPT® defines these services as care management services for patients with a single high-risk disease or complex condition. The existing chronic care management (CCM) codes require that a patient has two or more chronic conditions.
PCM (Powertrain Control Module) – This is a combined engine and transmission control unit which will provide management and correct function of the engine and transmission from one control unit. ECU (Engine Control Unit) / ECM (Engine Control Module) – This is an electronic control unit that manages the engine only.
More often than not, software concerns—not internal hardware problems—cause PCM issues. Other common causes of PCM failure include an overload from a shorted component or circuit, power surges, charging system problems, and environmental issues, such as moisture and extreme temperatures.
Check the voltage of the battery in the PCM using a multimeter. Set the multimeter to DC volts and connect its probes to the battery terminals. The reading should be around 12V. If it is lower than 10V, then check for any loose connections or other issues with the power supply before proceeding further.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

When replacing the ecu, do I have to have it programmed upon installation?
ANSWER : The PCM will need to be programmed if you have theft system that is factory installed. The PCM will need to be programmed to communicate with the theft module.

If I get my blower motor replaced, do I also have to have my Ac recharged after replacing blower motor?
ANSWER : The blower motor on this vehicle is a simple removal and installation and does not require anything to be touched on the A/C. The refrigerant does not have to be removed. The only component that has to be removed is the glove box under cover to get to the blower motor.

Do i need to replace the receiver drier and/or the expansion valve when replacing the condenser assembly?
ANSWER : Replacing the system drier is absolutely essential. If the system has been open to the atmosphere (due to the leak in the condenser), the desiccant in the drier has been fully saturated with moisture. As far as the expansion valve, replacement is not normally implicated in a leak repair, in your case a leak in the condenser. To justify replacing the expansion valve, there would have to have been a diagnostic performed which proved a fault. If no diagnostic was performed, and there is no evidence of a fault, then it is pointless to replace the valve. But, again, drier replacement is absolutely essential. To add the drier to your order, you can simply add a note to the mechanic in your order and/or add it as a service (you will see a link that you can click on to "add services" or write in specific services). If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

When replacing the AC Compressor, do I need to replace both expansion valves as well or just the front
ANSWER : Hi there. Anytime you replace major air conditioning system components like the AC compressor, it’s recommended to purchase all supporting hardware and replace it at the same time. AC works as a series of individual components working efficiently together to create cool air that flows into your cabin. As such, if you’re replacing the front expansion valve, it’s a good idea to replace the rear at the same time. This increases overall efficiency of the system, reduces the potential of small component failure and allows the parts you replaced to last longer.

Does the replacement of a thermostat include replacing the housing? I was told I needed to replace the thermostat housing.
ANSWER : Hi, thanks for writing in. The thermostat housing and the thermostat itself are two different components and do not necessarily need to be replaced together or at the same time. The housing is just a piece that covers the thermostat that also has an opening for a radiator hose which is where the water enters and exits the motor. The housing may need to be replaced at times if it is cracked or leaks severely, however they are indeed two different and distinct pieces.

Hope this helps and best of luck.

Does the whole steering column need to be replaced in order to replace a fried steering column module?
ANSWER : I would ask the mechanic for the exact part number of the electronic component that he believes has failed. Or, at least have him "name" the part and indicate where in the column assembly the part resides. The steering column is made up of many parts, most of which are separately serviceable. As discussed below, limp mode (reduced power) has many, many causes. Consequently I would also ask the mechanic to explain to you EXACTLY how he arrived at his diagnosis and ALSO have him show you the exact test results, on a diagnostic tool, multi-meter, or scope, that has led him to conclude that the particular "module" has to be replaced. With no evidence and no intelligible confirmation you would be taking a risk.

YourMechanic does offer a reduced power (limp mode) diagnostic. If you request a reduced engine power diagnostic the responding certified mechanic will give you confirmation of the cause of the issue in your case. Typically, a vehicle’s powertrain control module (PCM) will have stored one or more diagnostic trouble codes that will identify the "general area" in which the fault lies in the engine management controls. Although the throttle control system is a common trouble area with reduced power, there are quite a few other components and systems that could come into play and, of course, there is always the possibility of multiple, or "coincident", faults. Here are some of the possibilities that YourMechanic dispatched technicians would consider:

Defective throttle position (TP) sensor
Defective oxygen sensor
Defective accelerator pedal position (APP) sensor
Loose or damaged wiring
Defective throttle body
Defective powertrain control module (PCM) (not typical; ONLY if a long, long list of other possibilities is ruled out)
Any fault/error that will affect drivability function
Any fault/error that will affect vehicle performance
A fault/error in the emissions system
A fault/error in the throttle control system
A fault/error in the transmission control system

If you request the recommended diagnostic the mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Do I need to replace timing belt again of replacing water pump?
ANSWER : The water pump and timing belt should be replaced as a set if the coolant leaked on the belt. The coolant leaking on it will damage the belt.

Code P0011 problems
ANSWER : Hi there. P0011 is the OBD-II generic code indicating the engine control module (ECM) has determined that the bank 1 intake camshaft is more advanced than what the ECM has commanded it be. This over-advanced condition could be during advancing or retarding of the camshaft timing. I would recommend reading this article as it will provide you with details as to what typically causes this code to trigger, and possible solutions.