I got a BIG PROBLEM with starting in winter. I own MAZDA 3 (year 2004), I loves it to bits. But when temperatures drop below 0 (basically in winter only) my car does not want start.
Everyone was telling me it must be battery. But I was not sure, because it even wont try turn engine. But I got new battery and it did not solve the problem. My friends checked electric parts and it looks fine.
Then in MAZDA service told me to check IMMOBILIZER CONTROL if it is always on, or if it turns off when I get key in first position. Found out in cold weather it is always on and won’t let me start. So it is immobilizer problem we believe (Iam confused).
But when I cannot start I turn on ventilation in car for few minutes to heat up car and my immobilizer let me start after that. It is very strange. Or once I start in the morning, then my car starts ok until next morning day when it cools down everything in the car.
In MAZDA service they checked connectivity on ignition etc. and they sprayed connectors for good connectivity. But if it wont solve my problem until tomorrow morning what do you advice?

Did anybody have same problem [&o]? I hate winter. I am worried go anywhere that I wont start car

 

i havent had a problem whatsoever with my car. however this makes me wonder because there is no block heater. well at least i dont think there is one

 

Well, I really dont know. They might be somewhere cold joint (link) between immobilizer and ignition or somewhere there. Because cold joints are most likely visible in cold condition. When it is warm, electronic devises works fine, but when it is colder it might be problem. But where exactly might be my problem? If they had same problem in MAZDA service, it will be easier to solve it. But with this tricky situations might be problem anywhere ...

 

How would turning the fan on, without the engine on, warm up the car?

 

Yep my friend. Thats what I did. If you read above this sentence (but I called it ventilation sorry)...

But when I cannot start I turn on ventilation in car for few minutes to heat up car and my immobilizer let me start after that. It is very strange.

So I really do not know. Took it back to MAZDA service for testing again. I will see. But very tricky it is

 

That ws my point, and why I suggested that perhaps using other electrical devices (drawing from the battery) would do the same thing (perhaps?)

 

I am going to have to agree with Richard, pulling juice is warming something else up, and the fan motor is the second most draw on the electical system, Starter being first.

 

My dad gave a bit idea. What about if there is something wet around immobilizer because of winter (humidity if thats right word) and turning fan on will help to dry out something over there ... hm. Or other people adviced me to reset immobilizer in Mazda service.
I personaly think that immobilizer like it is is functional ( it wont needs to be change) but only some joints somewhere are not right....