Originally Posted by @!!narotordo

^Bump I never got them 3 codes when I put my catless mid pipe on

Originally Posted by always.anthony

wait so if we get a cel for our midpipe, this would clear it?

Originally Posted by RX-8newbie

if you erase the fuel trims, how do you relearn them...just drive cycles?

Originally Posted by RX-8newbie

ok, but...my problem is...its so bad, I dont think it would run well enough to drive around...

Originally Posted by teknics

edited 3/26: added addition KAM procedure, also formatted it for easier reading, removed some excess.

Hey guys,

Alright I seem to frequently be running into people suggesting you clear the KAM and/or NVRAM by holding the odometer/trip reset button and when it says test bla bla bla.

First of all, the only way to clear a code is with an OBD scanner or disconnecting the battery, CEL codes are NOT stored in KAM or NVRAM they are stored in basic memory in the module which they are set (PCM, TCM, ABS HU/CM, etc..). No power to the module with the code = no more code.

Here is how you clear your memory, also some reasons to clear each memory:

NVRAM (Non Volatile Random Access Memory)
NVRAM is a rather unique feature. The system memorizes the profile of the eccentric shaft plate on the e-shaft pulley. It basically knows how the e-shaft spins, on an individual basis, 2 cars NVRAM will generally never be absolutely identical, they're pretty close to unique.

As you'd imagine with such a specialized system you wouldn't want this information relearned and forgotten very easily, relearning the profile isn't a short process (drive cycle, dont worry you dont do anything special to relearn it). So this info is kept in a special area of the PCM it CANNOT be cleared in any way EXCEPT the proper procedure, you could disconnect the battery and do a jig for a year and it won't erase.

When/Why should you erase the NVRAM?
Realistically there are only a few times, generally the only times it's really needed is when replacing a motor since you'll be installing a new e-shaft position plate. Sometimes you'll also repair a misfire, yet the misfire code will return even with you not noticing anything, in those cases clearing the NVRAM will sometimes help. Also during PCM replacement it's good to clear it.

How do you reset NVRAM?
Here it is straight from mazda:

NOTE:2004-2008 and 2009 and later model year procedures are different.

2004-2008 Method

1. Turn ignition switch to "ON" position, but do not start engine.
2. Pump the brake pedal at least 20 times within 8 seconds after the ignition switch is turned ON.

NOTE:
Manual transmission equipped vehicles produced after VIN 40132647 and automatic transmission equipped vehicles produced after VIN 40132607 or vehicles with PCM updated to "L" calibration or later can confirm the clearing procedure was performed. If procedure was successful, the oil pressure gauge needle will move to right of center slightly (nearer H).
Vehicles produced prior to these VIN's or vehicles without "L" calibration do not have an indicator to confirm the clearing procedure was performed.


3. Drive vehicle and confirm misfire related DTCs are not stored.

NOTE:
If the malfunction cannot be corrected even though the procedure was successful, the eccentric shaft position plate may be damaged. Inspect the eccentric shaft position plate. Refer to MS3 online instructions or Workshop Manual section 01-40 ECCENTRIC SHAFT POSITION PLATE INSPECTION and repair as necessary.

2009-2010 Method

1. Record customer radio station presets (FM1/2, AM, SAT).
2. Disconnect negative battery cable for a minimum of 1 minute.
With negative battery cable disconnected, depress and release brake pedal one time.
3. Reconnect negative battery cable.
4. If equipped with DSC, perform the STEERING ANGLE SENSOR INITIALIZATION PROCEDURE located in MS3 online instructions or Workshop Manual section 04-15.
5. Input customer radio station presets.
6. Initialize power windows. Refer to MS3 online instructions or Workshop Manual section 09-12 POWER WINDOW INITIALIZATION PROCEDURE.


KAM (Keep Alive Memory)
Keep alive memory is not named because it keeps the car alive, rather it's named after the way it works. When you remove the battery terminals from the battery you'd assume all power in the car is lost right, hell your clock resets so the PCM must too, right? WRONG. KAM is saved by "Keep Alive" power, reserve battery power if you will.

KAM generally doesn't store very important stuff, other then the airbag operating on KA power they dont store anything in the KAM tho they just use the same reserve power. The main thing KAM stores are things like fuel trims etc. It's useful to reset KAM when you have lean/rich codes where the fuel trims have been able to reach 25%. It takes a while even after repair for the fuel trims to go back to proper levels, if you clear the KAM it will reset them to 0%.

How do you reset KAM?
Two easy ways, disconnect the battery and leave it like that for at least 10 minutes, sometimes longer. To expedite the process disconnect the battery and hold down the brake pedal, itll drain the KA power quicker. This will allow all codes to clear and KAM to clear.

After some research, at this time, it seems pulling the Room Fuse on the interior fusebox will also clear only the KAM. Not 100% sure yet, but pretty close.

-----------------

So what is this instrument cluster/odometer test thing people have been throwing around? The answer's right in front of their face, as it says it is a "TEST" and since it's in the Instrument cluster it would be.........the Instrument Cluster Input/Output Check Mode.

What is the IC Input/Output Check Mode? It's a quick and easy way to test all the electric meters/sensors/lights etc in the IC.

Here's a link to a larger description:
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-diagnostic-outputs-155947/

YOU CANT CLEAR ANY PCM MEMORY WITH THE ODO/TRIP RESET BUTTON. If you want i can explain how to test each on of those things... im still searching for where in the FSM it says the odometer can reset NVRAM, because im sure mazda would like to repair it.

Thank you and good night,
kevin.

Originally Posted by TeamRX8

No way to really bent the e-plate.

Originally Posted by Mazurfer

^....................well, that explains it!
Jeez, what was it...welded on there?

Thinking if he didn't pry it off with a freaking screwdriver(if stuck at all) that maybe he didn't get it lined up with the holes correctly? Think you would see that as a distinctive wobble and car won't react well. Better check it and clean that sensor.

Sergio...........When you did the reset, did you see the oil gauge sweep right and then left? If not, do it again and repeat until it does(assuming you checked everything else).

Originally Posted by teknics

the radio button reset is only for audio related DTC's, there's a whole sub-test system for the audio system.

there's tons of different memory resets, one for almost every module on the chain. only the NVRAM and KAM are engine related, other then PCM regular memory etc.

kevin.

Originally Posted by caidoz

I haven't had my 8 for a super long time and when I got it, it had bad a bad cat and weak coils. I replaced the exhaust with a Turboxs and rp. Then I replaced the coils with the BHR kit. Car runs good but there is a wierd hesitation at around 6k. It was alot worse with the bad coils. It kinda felt like a fuel cut with the bad coils now it just feels like a slight hesitation. I was wondering if it could be fuel trims from having the bad coils. I'm only getting a cel for the no cat. Thanks in advance for any help or Ideas.