Mazda6 that shuts off while driving and instrument cluster goes crazy!

So I was driving to work and I was on the road for about 40 mins when the engine shuts off. All headlights, radio, subs, blinkers, windows are all operating normal when this happens. However the speedo and rpms and sweeping back and forth, all warning lights are on but the security light and check engine light are flashing. So I get out and pop the hood and mutiple things are clicking. The throttle body is clicking, relays in fusebox clicking, valve by airbox clicking. If I turn the key off and wait about a minute, it will start right back up. But as soon as I drive about 5 miles its shuts off again. I let is sit for a minute, it starts up again. It seems if I let it sit overnight I can get about 40 mins of driving before it stops running..So the battery and alternator are brand new and its still doing the same problem. Nothing has changed. I printed wiring schematic and found all the ground wires in engine bay, disconnected and clean all of them, still same problem. Only thing I can think of at this time is the PCM. Has anyone seen or heard anything crazy like this?!!!

Well if its doing all that im sure it has thrown a CEL or two... what are they? Also we will need more on your car.... model, trans, mileage, ect.. ect...


Edit: I see you have a 04 Mazda 6 hatch with Bose but what engien and trans? I also I see you were trying to hook up a sub to your bose system. Did you do that? If so disconnect it and see what happens(you never know its worth a shot). Did you ark any wires during the install? We need more info man.

Ok, so its 2004 V6 manual trans, System was installed by Best Buy and has been installed for 5 months now. Disconnected system and problem still occuring. The check engine light is never on, still scanned for codes, and found a loss communication code can BUS. Thats it nothing else. I can communicate with all modules on vehicle, clean and tightened all grounds in engine bay..I dont know what else...Its at the dealer now and they cant come up with anything!!!

Hey hopeless this is a huge mystery for us... (yes Im the service advisor on your car ) Weve run the gauntlet on possable causes for whats going on with your car. Tech whos diagnosing it has over 30 yrs with mazda and this is the first time he's come across something like this... He was on with Mazda techline till after 6pm last nite.
All I can say is were trying our best to get your car straight........

If your ECU is losing CAN bus communication that should mean a loose or intermittent connection somewhere, probably heat related because it went away after the car cooled down. Check your ECU connections maybe? Make sure various electronics aren't overheating for any reason. Good luck.

could this be caused by a failing body control module?

Possable resolution to his problem has been found. Will post more info when its verified...

Hopefully PCM will fix it. Thanks again!!

i had the same problem just now. and i dont know what to do. please help..

Hello,

I have very similar issues with my 2005 Mazda 6S (V6 automatic 6-speed). My instrument panel flashes on with CEL when driving the car for ~1 hour or more in stop and go conditions on very hot days. I had the fan control module replaced a few years ago so I am not sure what could have failed to allow an overheating condition.

I would love to hear the answer to the original posters issues.

I had this exact problem and it turned out to be my alternator. I would def check it out...

What was the resolution to this? I have a 2009 that is doing the same thing. The Mazda Tech is baffled

Many Thanks!

VRMS6 said:

Possable resolution to his problem has been found. Will post more info when its verified...

Click to expand...

Hi, What was it, mine is doing the same thing!

paulr said:

What was the resolution to this? I have a 2009 that is doing the same thing. The Mazda Tech is baffled

Many Thanks!

Click to expand...

I had a similar problem with my Mazda 6 2003 2.0 diesel except there was no clicking, the error was about losing CAN communication. This would happen usually when the car heats up after about 100-500 km drive, turning on the AC or driving more aggressively seemed to make it happen more often.

My mechanic tried all sorts of things: replacing the battery, rearranging relays, replacing the camshaft sensor. Nothing helped.

Until I changed the timing belt, which made the problem appear WAY more often - every time as soon as the car heats up (after just 5-10 km). So, back to the shop and this time I wasn't leaving until we get this problem fixed! So my mechanic instructed his employee to check the wiring - follow the CAN wires from the ABS/DSC module to wherever they go.

Eventually we found out that the CAN wires go under the windshield fluid container and into the webasto heater. A place where the mechanic had been working recently, because he had removed the windshield fluid container to change the timing belt. We inspected the wires and voila! The wires go right between the container and an AC tube/pipe, the container rubbing against them and that's exactly where the insulation of the wires was damaged! Cut the damaged part and connect them back together - problem solved!

I guess Mazda realized this was a weak point because they moved the windshield fluid container closer to the headlight in the 2005 facelift.

I hope this helps somebody else.