PCM Adaptive Memory clear or ECU reset
09-22-2016, 04:58 AM
#1
JK Newbie
Thread Starter
Join Date: Dec 2011
Location: Grovetown, GA
Posts: 76
Likes: 0
Received 0 Likes
on
0 Posts
PCM Adaptive Memory clear or ECU reset
Seen this on another form has anyone tried this on a JK?
This very simple procedure will Erase the “Adaptive Memory” stored inside the TJ PCM and allow a new “Adaptive Memory” to be developed.
After performing this procedure the PCM will re-learn and store into Adaptive Memory your engines performance characteristics.
Please perform these steps exactly as they are written, in the order they are written. This will cause the adaptive memory in the PCM to be erased and cause the PCM to go into Fast Learn Mode adaptive mode.
Disconnect the POSITIVE battery Terminal and touch it to ground for 30 seconds. (This is to discharge the PCM capacitors, which maintain the Adaptive Memory.
Reconnect the Battery Cable
Turn Ignition Switch to the “On” position but DO NOT start the engine
Turn Headlight “On”
Turn Headlights “Off”
Turn Ignition Key “Off”
The PCM Adaptive memory has now been flashed, or erased from the PCM.
When you start the engine it will be running off a set of pre-programmed tables that come with the PCM from the factory.
When you get the engine up to operating temperature the PCM will start to collect data for the “Adaptive Memory”.
The PCM will collect data for Adaptive Memory for the first 50 Warm-up Cycles.
Warm-up Cycle
A warm-up cycle happens when all of the following conditions exist.
Engine is running
A raise of 40F in engine temperature must occur ABOVE the engine temperature at start-up
Engine Coolant Temp must reach at least 160 F.
Once your engine has gone through 50 warm-up cycles in at least a 500-mile distance the PCM adaptive memory is set.
It WILL NOT Change unless you flash it out and start all over again.
This very simple procedure will Erase the “Adaptive Memory” stored inside the TJ PCM and allow a new “Adaptive Memory” to be developed.
After performing this procedure the PCM will re-learn and store into Adaptive Memory your engines performance characteristics.
Please perform these steps exactly as they are written, in the order they are written. This will cause the adaptive memory in the PCM to be erased and cause the PCM to go into Fast Learn Mode adaptive mode.
Disconnect the POSITIVE battery Terminal and touch it to ground for 30 seconds. (This is to discharge the PCM capacitors, which maintain the Adaptive Memory.
Reconnect the Battery Cable
Turn Ignition Switch to the “On” position but DO NOT start the engine
Turn Headlight “On”
Turn Headlights “Off”
Turn Ignition Key “Off”
The PCM Adaptive memory has now been flashed, or erased from the PCM.
When you start the engine it will be running off a set of pre-programmed tables that come with the PCM from the factory.
When you get the engine up to operating temperature the PCM will start to collect data for the “Adaptive Memory”.
The PCM will collect data for Adaptive Memory for the first 50 Warm-up Cycles.
Warm-up Cycle
A warm-up cycle happens when all of the following conditions exist.
Engine is running
A raise of 40F in engine temperature must occur ABOVE the engine temperature at start-up
Engine Coolant Temp must reach at least 160 F.
Once your engine has gone through 50 warm-up cycles in at least a 500-mile distance the PCM adaptive memory is set.
It WILL NOT Change unless you flash it out and start all over again.
09-22-2016, 12:03 PM
#2
JK Enthusiast
Just be careful if you live in a state with a Smog check test and it is coming up soon. That will clear the OBDII and a complete drive cycle will need to be done to get the computer ready for smog testing.
09-22-2016, 04:36 PM
#3
JK Jedi Master
Is this something one would do just for the heck of it? What would be the reason to do this?
Does the JK PCM remember any engine characteristics other than the Adaptive Numerator, which has to do with the crankshaft position tone wheel?
There is nothing like this procedure in the JK service manual.
The JK TCM does remember certain things about the automatic transmission, such as clutch fill time, clutch pressure, shift time, and torque converter lock-up control. This memory is stored permanently.
"Driving style" adaptation is for the moment, and has no memory.
Does the JK PCM remember any engine characteristics other than the Adaptive Numerator, which has to do with the crankshaft position tone wheel?
There is nothing like this procedure in the JK service manual.
The JK TCM does remember certain things about the automatic transmission, such as clutch fill time, clutch pressure, shift time, and torque converter lock-up control. This memory is stored permanently.
"Driving style" adaptation is for the moment, and has no memory.
09-23-2016, 05:30 AM
#4
JK Newbie
Thread Starter
Join Date: Dec 2011
Location: Grovetown, GA
Posts: 76
Likes: 0
Received 0 Likes
on
0 Posts
Is this something one would do just for the heck of it? What would be the reason to do this?
Does the JK PCM remember any engine characteristics other than the Adaptive Numerator, which has to do with the crankshaft position tone wheel?
There is nothing like this procedure in the JK service manual.
The JK TCM does remember certain things about the automatic transmission, such as clutch fill time, clutch pressure, shift time, and torque converter lock-up control. This memory is stored permanently.
"Driving style" adaptation is for the moment, and has no memory.
Does the JK PCM remember any engine characteristics other than the Adaptive Numerator, which has to do with the crankshaft position tone wheel?
There is nothing like this procedure in the JK service manual.
The JK TCM does remember certain things about the automatic transmission, such as clutch fill time, clutch pressure, shift time, and torque converter lock-up control. This memory is stored permanently.
"Driving style" adaptation is for the moment, and has no memory.
***UPDATE****
So... I stopped by O'reilly's on the way home and shot the shit with the manager and he said this does work and is safe. Just make sure you take both +/- off the battery when you touch them together. The reason I tried this is because I cleaned the throttle body plate due to my Electronic throttle control (ETC) light --> )Z( coming on and have been trying to troubleshoot it. Some people say that flashing the PCM after cleaning the throttle plate forces the PCM to learn the new trim levels of the cleaned throttle plate. After doing this the light has gone off and hasn't come back on after 150mi. Hope this helps!
Last edited by puppetmaster; 09-26-2016 at 05:29 AM.
09-23-2016, 05:33 AM
#5
JK Newbie
Thread Starter
Join Date: Dec 2011
Location: Grovetown, GA
Posts: 76
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the pointer! Luckily I live in a state that doesn't have smog checks.