2007 Mazda3 2.0L no crank, no start

[InfoReqdPls?]

2007 Mazda 3 2.0L, no crank, no start issue. When I try to start the car it clicks once in the fuse box under the hood. Scan says CAN BUS not communicating. All lights, instruments working just no crank or start. Looking for ECU pinout as well. Any info is appreciated, thanks.

 

[edmaz]

Always best on these problem threads to summarize what you've already tried, so that we all don't waste time suggesting what you've already done.

 

[concept]

The first thing I would check would be that the battery post clamps are tight. If they are, then verify the date sticker on the battery. My son was ready to jump start or charge up his battery when I suggested he check his battery's date code. It turns out that the battery was 5 years old. He removed the dead battery and took another car to take it to Costco for a replacement.

 

[negusm]

Yeah, start with the simple stuff. Has the battery been tested/replaced? Tight battery terminals? Uncorroded battery terminals and cables?

 

[InfoReqdPls?]

Always best on these problem threads to summarize what you've already tried, so that we all don't waste time suggesting what you've already done.

@edmaz, I would have to agree, I should have stated what I had already tried. Not an excuse but I was beyond frustrated that day.

So anyway the problem ended up being a broken connection from the fuse box to the ECU and of course once I finish fixing that the starter solenoid went out so had to replace that.

 

[concept]

Any guess how connection failed? That seems odd.

 

[edmaz]

@edmaz, I would have to agree, I should have stated what I had already tried. Not an excuse but I was beyond frustrated that day.

So anyway the problem ended up being a broken connection from the fuse box to the ECU and of course once I finish fixing that the starter solenoid went out so had to replace that.

No problem, because everyone in the DIY community understands about getting frustrated. Good to read that you eventually were able to get it fixed!