ABS/DSC/PCM probs 2004 Rx8 6MT NEW ENGINE!
 

Just bought an rx8 few months ago got a new engine done to it pay in 6g CASH!! and a used tranny works great no more noise feels like brand new but im stuck with one last issue
I got a code U0073 CAN communication bus fault and U1900 CAN communication fault-receive error
I have brand new rotors and brakes done to it. 3 weeks after it pops out while driving and sometimes on a cold days it doesn't pop out and on a hot weather days right from the start up it lights were on both ABS and DSC lights on. Need help to fix this or if someone got the same issue pls contact me or any advice.. I called mazda dealership Kramer in Calgary and I guess they've been dodging my calls coz I did a tons of research about them resetting my PCM or something free of charge.

The communication errors are almost always errors between the ECU and the device used to read it. Communication errors are only ever important if you can get the same error between multiple different devices. I recommend verifying with at least 3 (different shops or your own or friends, etc...) if you think this is actually a problem.


The ABS and DSC lights will come on when the ABS/DSC/TCS detect wheel speeds that don't make sense. This can be a wheel speed sensor failing, though it is usually just a difference in the rolling circumference of the tires. Usually this is a tire pressure variance between one or more tires. Ambient temp can change the air pressure of the tires, so it's possible that it takes the higher pressures from warmer air before it sees a problem. Go around and check all 4. I bet one is much different than the others. This can also pop up if the tire pressures are fine, but you have different size tires front and rear, left to right, something, so compare the sizes of each tire. One tire excessively worn could also produce the same effect.

Thanks for lots info. There was one time I went for a party and someone popped my tire on the rear driver side. So the next day I went to find the same tire brand and tread but there's none so I ended up buying a tire with a different tread.. but I recently bought set of rims and tires with all brand new and I'm still getting the same lights.. typically on a hot weather.. I have the tire pressure always checked since I work in a dealership..

I do noticed when I'm at full stop or the engine not even running the speed reading goes 2 4 5 and back to 0.. so I got Into a point that it might be the speed sensor

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So I have the same issue with the OBD but my issue is that I had and interested purchase of a rad cap online says it fits but I ended up getting coolant out reservoir and a decent humidity under the hood should Also, I forgot to mention she is my only car and I gotta be at work in about three hours.