Battery going flat

mas

Junior Member
Messages
46
Hi,

My battery keeps going flat due to a 180mA constant drain. Based upon this rate the car will not start after about 9 days. Battery is new and correct rating, the NavTrack unit is not connected.

Investigation points to the fuses F43 / F44 which relate to the passenger & driver power windows, but it appears theses fuses also control the door locking component in conjunction to the "Glass lifting Control Unit" as located within the passenger foot well?? When fuses F43 / F44 are removed the current drawn from the battery is virtually zero.

Searching on this forum somebody else had the same issue but the response suggested checking the micro switches within the doors, unfortunately there was no conclusion whether this was successful.
I am not sure if the micro switches is the culprit. The door locking does work and there is no issue with the operation of the electric windows including the "auto" drop / rise of the door glass when opening or closing the doors.

However what I did notice is a slight warmth of the "Glass lifting Control Unit" (part No. 192673) in the upper left section. (within the physical unit this is where the relays are located but I do not think they can be dismantled.

Mas
 

Mike Maz

Junior Member
Messages
32
Good day Mas, are you you sure that it's still 180 mA after 10 minutes as it takes a bit of time for the system to go to sleep? I spent days trying to trace a similar drain because I wasn't giving the system time to shut down! Hope this helps
Mike
 

mas

Junior Member
Messages
46
Mike,

I have left it for hrs and it still has the 180mA drain, I even purchased a dedicated amp metre just to 100% make sure.

Mas
 

davy83

Member
Messages
2,809
Sounds like the "warm" window controller might be telling you something? Certainly if the micro switches were causing the window motors to be on all the time this would draw a lot more than 180mA. Also window power should be off once the doors are closed and the ignition off, so not sure why this power is even on, its possible the relay that supposed to shut the power off is faulty leaving the window circuits live. can you wind down the windows with the doors shut and the ignition off? this should not be possible, it should work with the ignition on, and also with the doors open (regardless of state of the ignition).

Hi,

My battery keeps going flat due to a 180mA constant drain. Based upon this rate the car will not start after about 9 days. Battery is new and correct rating, the NavTrack unit is not connected.

Investigation points to the fuses F43 / F44 which relate to the passenger & driver power windows, but it appears theses fuses also control the door locking component in conjunction to the "Glass lifting Control Unit" as located within the passenger foot well?? When fuses F43 / F44 are removed the current drawn from the battery is virtually zero.

Searching on this forum somebody else had the same issue but the response suggested checking the micro switches within the doors, unfortunately there was no conclusion whether this was successful.
I am not sure if the micro switches is the culprit. The door locking does work and there is no issue with the operation of the electric windows including the "auto" drop / rise of the door glass when opening or closing the doors.

However what I did notice is a slight warmth of the "Glass lifting Control Unit" (part No. 192673) in the upper left section. (within the physical unit this is where the relays are located but I do not think they can be dismantled.

Mas
 

CatmanV2

Member
Messages
48,557
Yep. My money would be on a door solenoid failing. Could be totally wrong, however.

Try disconecting each in turn, see if that kills the current drain.

C
 

conaero

Forum Owner
Messages
34,594
Bosch S5 096 on special at ECP for the next 24 hrs with code: SAVE75

£85 plus vat

Bagged one myself.
 

DevonPaul

Junior Member
Messages
76
I had this problem a while ago, solved over winter by getting a CTEK trickle charger.

At Ftech last Dec it was reading a 400mA drain when locked, and the battery was struggling/failing to start the car after 3 or 4 days.

So, at the weekend I bit the bullet, and met a mate who is a Ford research/design engineer and he came out armed with a box of tricks and all the tools required to dismantle and test large amounts of vehicle electrical bits.

Clipped on ammeter - 40mA.

Unlocked door - brief spike to 20A as the clutch pump primed, then dropped to 40mA.

Opened door, same result.

locked door, got a 200mA drain for about 30 secs, then down to 40mA Same locking the door with the key.

Also tested the battery and measured the voltage under different loads and charging conditions - all fine.

So it appears the solution was to ignore the bugger for 4 months then blat over some Welsh mountains to dislodge whatever was sticking and causing the drain.

What's the betting it will be flat on Friday?

Paul
 

mas

Junior Member
Messages
46
Paul,

An interesting solution, but it's a long drive from Sydney to the Welsh hills! Reminds me when I lived in Cardiff.

My plan is to swap over the "Glass lifting control unit" at Maserati/Ferrari service centre as apparently this is know as a potential cause. Note sure if I can get it done this week. But will let everybody know the outcome.

Mas
 

conaero

Forum Owner
Messages
34,594
Just to update you:

Fitted the new battery on the Strad yesterday...twice!

Bought the recommended battery from ECP Bosch Silver S5 096, 79ah/790CCA...wrong!

It should be an 017 100ah 900CCA and it's 120mm longer so be warned.

Bosch only do a S3 and it's not up to OEM spec so went for an Exide branded.
 

mas

Junior Member
Messages
46
All.
Thought I should share the conclusion of the flat battery.

I originally suspected it was the window control unit. So I took the car to Maserati specialist garage they said they would swap it over with another control unit. As it turned out it was not the control unit but the driver side micro switch that was sticky.
I originally checked the passenger door micro switches but decided not to check the driver side unfortunately.

I no longer have the battery drain issue after fixing this about 6 months ago.
 

GraemeA

Member
Messages
108
Mine drains over 4 days plus. I just disconnect the battery and reconnect it when I use it. Only slightly annoying.
 
Messages
1,117
But you have a fault. Disconnect is a work-around but does not address the cause. Surely, the cause needs to be found and rectified???