Hello everyone,

We have a 2014 Mazda 6 with 97k miles on it that is throwing so many codes its stumping the mechanics.

Background:
- Oil change done in early June, confirming full coolant
- Serpentine belt replaced in August
- New battery replaced in August, some corrosion on the terminals
- For quite a while the shifter needs to pulled toward the "P" position for the whole car to shut off, I think its just the degradation of a small plastic part in the gear shift.

Scenario:
- Continuous driving for ~5 hours through 100 degree weather on the freeway - AC blasting the whole time, a couple miles from home (still on the freeway) the radio unit and dash reset & car went into limp mode. SCBS sensor code and check engine on the dash. Got it home and car seemed to leak more liquid than what seemed like normal AC condensation. Radiator fan continue for quite a while after and coolant was extremely low when checked later. (Not confident that this has anything to do with the current issue but providing all details)
- Drive to Mechanics started out fine, then went into limp mode and had a full shut off after about 10 min. Restarted after 1 or 2 min off.

Mechanics (Japanses auto shop) let us know about the following codes that it was throwing, but they don't know what is wrong with it and recommend we tow to a Mazda dealer....took them a week to do this. They killed the battery not fully shifting it into park (see background above), and are saying its an issue with the radio unit staying on and draining the battery. This doesn't make sense to me based off the first scenario of highway driving.
Codes: (File attached with descriptions just from google).

• P0882: 00-28
• U0401: 00-28;
• U0433: 68-08;
• U0515: 00-08;
• U3003:16-08;
• P0882;
• P2610;
• U3003

Any thoughts on what we should ask the Mazda dealership about checking first? Would love to not have endless diagnostics.

 

Hmm .. so they are not the best at diagnosis OBDII systems then??
Ok then .....


First after confirming by way of load testing the battery to make sure the battery passes and that all the leads are cleaned and connected well.
If you don't do this then it is vital first step and I cant help you!

Then forget all the DTC info. Its to much and over lapping DTC that may be because to many cycles from the original DTC

So get back to base lone. Connect to the diagnostic port (NO BLUE TOOTH direct connection only) Clear everything and reset the I/M Monitors.
If you miss those 3 re-set/clear I cant help you.

Now and only if the Mazda has not been started until the next day so nothing get conflicted and you start out with a new engine cycle start the engine. If the engine warms and does not activate the check engine light good. Now go for a short drive.
Basically as soon as the check engine light is activated scan and retrieve the DTC in DTC pending and permanent file area. Have a look at the IM Monitor and see which are now green or in state of read.
Make notes and report the findings.

Any deviation or not completely these I wound not be able to help you. At least by trying to do what really should be a physical diagnostic service.
It is smelling like a ECU and or TCM failing but that is a guess on all that info you are posting. And it could be as simple a dirty connectors to the ECU? or even the main battery is failing and bad connectivity (poor cable connection etc., etc., etc.

 

Welcome to the forum