Possible problem with "M" flash
 

Got the M flash last week and could tell an immediate difference in throttle response and midrange, however, last night I got cel light for ABS, Brake, and traction control when I restarted the car the cels went out but I took it into the dealership and when they ran the codes the tech called Mazda to find out whet they meant. They told him that because I have aftermarket wheels without the tire pressure sensors, and a K&N Intake the PCM is not functioning properly, because it is trying to read the tire sensors to adjust for speed etc. I have 12,000 miles and have never had this problem prior to the M flash. So far the cels have not returned but it took about 500 miles after the reflash before they apppeared. Anyone else had this problem? Any recommendations?

Re: Possible problem with "M" flash
 

Bull crap. The PCM uses the ABS sensors to determine road speed and variations side to side and front to rear (for the stability and traction control systems). The TPMS has absolutely nothing to do with speed sensing.

The K&N intake, on the other hand, could be part of your problem. Some of the other K&N intake owners have reported problems - perhaps you should try a search here to see what's been going on.

Regards,
Gordon

5150,

Try and find out the codes the PCM set.

If you have (significantly) different sizes of tyres front and rear (larger circumference), it can indeed trigger a CEL as the PCM should read same wheel speeds for all four wheels most of the time. If not, the PCM believes something is wrong with one or more wheel speed sensors.

An aftermarket intake can also trigger a CEL due to increased measured mass air flow (due to different flow pattern across the section of the MAFS, not more air unfortunately). That measured air flow could be now beyond the maximum defined as due to a Mass Air Flow Sensor malfunction.

IKN

Got the 3 brake/traction/ABS lights once this winter while stopped at a light. The ABS was NOT working when I pulled over in a snow covered lot. Shut it down and restarted with no problem.

Stock everything.

Never happened again

I've seen the same 3 warning lights several times but always at the same location: getting on or off the parkway near my home. The problem always cleared up after restarting the car. It hasn't happened recently because I can't drive past that spot any more due to road construction. I figure it's either a glitch in the electronics, or radiation from the secret labs in the nearby government office complex!

Tire diameter is the same all around, so that shouldn't be a problem. The codes are C1222, U2616, U2617, U2618, 2619

those i think a communication errors. the lights are coming on because it cant communicate with one or more sensor. how long have you had the wheels?

I also had those lights come on once, on an on ramp. Here in Canada, there are no tire pressure sensors, so that is not the problem.

The dealer checked this week, and there were no codes in the ECU.