Q: does my key have to be programmed to new ecm

asked by on

I think my ECM is bad..code p705 and p0302 read w scanner multiple times. Had diagnostics ran at dealership, was told faulty neutral safety switch (transmission range sensor) and coil not plug on cylinder2. I've replaced sensor and coil and wiped codes from memory and now codes still present along with p0110 p0100 p0101 now. Dealership rule outs for p705 were the sensor and the ecm...my car doesn't seem 2 kno what gear it's in and it's mimicking transmission issues...if I get a new ecm do I have to program my key to it or will it need the same type of chip that's already in my key?...and is a ecm a reasonable culprit for my issues?

There is a long, long decision tree in the Factory Service Manual (FSM) to deal with issues like the one you have and it is only at the very end of that tree, that you consider ECM failure. Indeed, ECM failures are so rare that half of all ECM’s returned to re-builders as "warranty exchanges" are in fact perfectly good. If ECM failure is suspected, if you are working with a Toyota dealership all they have to do is swap in a known good ECM to rule that component in or out. They could also first try re-flashing your ECM (that’s easy).


The point is there is a lot to rule out and in your case you have several powertrain codes available, that if tracked down and resolved, could resolve the symptoms you are having. What I suggest is you request a check engine light diagnostic. A certified mechanic from YourMechanic would track down the causes of the three codes you have cited and first get that resolved. If problems continue, the mechanic would just simply follow the remainder of the decision tree in the FSM until this is resolved. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. does my key have to be programmed to new ecm

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Can a bad fuel pump cause overheating and loss of coolant.

Hello. We will be happy to help you. The coolant system and the fuel system are unrelated. If one is malfunctioning it will not have an effect on the other one. The fuel pump is also not belt driven, I...

Q: What does the NO MUSIC USB error mean?

When you connect a USB device to your sound system and receive the “NO MUSIC USB” error, it means that the device does not have any compatible MP3 or WMA music tracks on it. If it fails the first...

Q: Car's electrical completely dies at first crank. Battery is brand new and has been tested at 505 amps.

Hello, thank you for writing in. Electrical issues like this can be tricky. The first thing you should try is starting the vehicle with another battery. Pull a known good battery from another vehicle, and try it in your car...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.