newbie needs help

[hoodiehiker]

I have a 2003 325i that i am having multiple electronic issues with and I need to learn how to fix them.

1) Heater - takes forever to heat up and only stays warm while driving. if i am stuck in traffic and not moving it becomes cold again.

2) door locks - don't lock any longer - or more accurately they don't unlock...

3) The heat doesn't seem to change velocity when i turn up or down the fan...


If you have any ideas of where i should start with any of these issues I really appreciate it.

[02Pilot]

#1 is very likely not an electrical issue, but the thermostat stuck open. Your car, unless it's been done already, should have the entire cooling system replaced. If it fails in a way that causes overheating, you will be buying a new engine. This may sound alarmist or exaggerated, but it isn't.

I'm no use with #2. As to #3, we need info on whether you have manual or electronic climate controls.

I very strongly recommend you buy a Bentley manual for your car. If you plan on doing any of your own work, you need this.

[shadowpuck]

https://www.bimmerforums.com/forum/s...ose-your-issue
https://www.bimmerforums.com/forum/s...cal-Help-Forum

agreed with 02pilot. most likely overdue for cooling system maintenance, and, if an automatic transmission car, fan clutch is probably due too.

door locks could be any number of things - ranging from fuses to the GM (general module) acting up. what have you done to troubleshoot this issue?

agreed on #3 - if auto climate controls then this is likely a final stage resistor issue.

[hoodiehiker]

Thanks for the heads up on overheating of the engine... I know that spells bad things to the engine. I didn't realize that could cause overheating.

Here is some more info for you -
113k miles
auto Transmission
i don't think the cooling system has been replaced.
there is some slipping when the car is cold moving from reverse into drive - takes the car a moment to catch the gears it seems...
My father was a foreign auto mechanic so i grew up turning wrenches but def am out of my league here...
The locks i think are more stuck than anything else i think...

- - - Updated - - -

sorry probably stupid question but "cooling system" - are you referring to the engine cooling system? or the AC?

[WadiM3]

Engine cooling system

[bmwdirtracer]

Yeah, um, you need to replace the : thermostat, water pump, radiator, expansion tank and cap, all the hoses, and the two plastic coolant pipes under the intake manifold, and the fan clutch, if the car is automatic trans.....that's the cooling system replacement being referred to here. Make sure to vacuum - fill, the system, or follow the correct bleding procedure in the FAQ sthread at the top of this forum.

Door locks: Well, you need to connect the car to a BMW specific diagnostic computer, and try commanding the locks from that computer. Maybe you've got a bad ZKE (body computer); maybe you've got bad door lock actuators, maybe the remote batteries are dead.

For #3, replace the final stage resistor; one of the most common failures on any BMW of this era. Don't even think about it, IT IS BAD.

[MarcoZandrini]

Let me add to the great recs provided to you. If the car has an auto tranny you’ll need to replace the tranny fluid cooler that’s connected to the cooling system. Why? It’s made of plastic and at that mileage it’s become brittle. It’ll break when you go to remove it from the expansion tank mounting bracket. I have to ummm disagree (sorry Chris) with the rec that you replace the plastic cooling system pipes under the intake manifold. They’re good for about 200k miles. Sorry Chris!!