440 Flat Batter (Again!)

[nano]

Originally Posted by Bruce_T

I dont mean to come across as obnoxious.

Im below a rookie level at this stuff and only recently bought one of these.

If I take a picture of the device in question maybe you could give me some pointers so I can check again to a greater depth?

Ok, I can see the current socket (2 A Max) and the 10 A. The latter is dedicated to the 10A dial. I you want to use the dials 200 uA - 2 A you must connect your probe to the 2A socket.

Any way, this is not your problem. The 0.22 A leak is about 10-100 times bigger than the expected from a stand-by system.

In my opinion, a troubleshooting process should start by unplugging fuses form the fuse box measuring at the same time the drawn current, first starting with the less critical (lights, blowers) and last the ECU fuse.

[Bruce_T]

Thanks.

Ill do this tomorrow in the day light and post my findings.

[nano]

Originally Posted by Bruce_T

Thanks.

Ill do this tomorrow in the day light and post my findings.

Dont forget to reinstall a fuse after checking it. And also, dont stick at any change in the last digit of the reading during your test.

[Bruce_T]

Out of interest do you get different result from the multimeter been in series at the +ve side instead of -ve side?

I have this afternoon off so I'm just going to start at the top left of the fuse box and work my way along.

[Bruce_T]

Ok, nano - Here are my findings.

I have a 92 onwards 440 so the fuse layout is different to the 88-91 440.

Top row of fuses didnt touch the current drain.

But one did a HUGE drop on the bottom.

Remember I was around 210-215 drain?

I removed fuse #21 and it dropped to 35-37!

So, whats on fuse 21?

The panel in my car says the following;

centr
doorlo
clock
glove
box la
radio
b+


I disconnected the clock, not that.
I removed the bulb from the glove box, not that.

So where left with the radio and centr doorlo which I think is central locking?

Ive removed fuse 21 and tried to lock the car with the fob, it locks but the LED on the dash stays lit. But all doors are locked.
I cannot set the alarm off though. Not a big deal at the moment. The central locking works fine though. I disconnected the siren it dropped from 37 to 33.5 ish also.

According to haynes, fuse 21 is the following;

Central locking system, keyhole light, glove box light, radio memory (RHD radio power supply) and clock.

So on that assumption I know its NOT the glove box light and not the clock.

So its something wrong with my radio (Its an aftermarket alpine one) and/or the central locking system.

Ill remove the radio later and see if its that. If not, then the central locking system (I think the module ?) will need replacing.
Whats the keyhole light? The green ring of light around the ignition?
Ill have a look and see if I can disconnect that to rule it out also.

[Bruce_T]

Ok, weird.

Fuse 21 in everything connected as normal

210-215

Fuse in and radio disconnected.

56-58

Fuse out 35-37.

So, some wiring is a miss it would seem.

My head unit is fine. I suspect a previous owner has bodged some wiring from what I can tell.

Now im stumped as I cant fix wiring!!

[nano]

Out of interest do you get different result from the multimeter been in series at the +ve side instead of -ve side

Some times there is a difference in the last digit.

Originally Posted by Bruce_T

Ok, weird.

Fuse 21 in everything connected as normal

210-215

Fuse in and radio disconnected.

56-58

Fuse out 35-37.

It seems your radio drains a lot of current at stand-by. As far as I know, when the radios are off drain only a very small current (of less than 1 mA, 0.001A) to retain memories and other settings.

The 56-58 mA look reasonable! With this current the battery would get half-flat (to half of its capacity) after 25 days, and at this charge is capable to start the engine for a few times.

[Bruce_T]

Thanks Nano.

I do not think its the actual head unit, but the wiring its connected to as its been in 2 other cars with no problems.

Something to try and attempt to suss out another day I think by someone who understands the wiring of the radio a little better I think!

[nano]

Originally Posted by Bruce_T

Thanks Nano.

I do not think its the actual head unit, but the wiring its connected to as its been in 2 other cars with no problems.

Something to try and attempt to suss out another day I think by someone who understands the wiring of the radio a little better I think!

Ok. You can measure the current of the radio itself, by connecting the meltimeter leads at the fuse socket of radio.

This will give the current drawn from the radio only.
Also measure this current with the auto-antenna cable disconnected.

[Bruce_T]

Oh, interesting. I can test the head unit using the same setting on the multimeter as I was on the battery? Ill report back with that info tomorrow.

The antenna on my car is disconnected. I removed the power cable from it as it doesnt fully go up as some of the sections are bent...
Couldnt be that could it?