Central locking circuit leak

Technical questions and answers about the Mazda Bongo

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spout

Central locking circuit leak

Post by spout » Wed Oct 15, 2008 4:42 pm

From what I’ve read on this forum and the fact sheets I’m assuming that our Bongo has factory fitted central locking and the “remote” has been added at a later date (the key fob certainly looks after market).

I am trying to trace a 0.05A drain through the circuit that the central locking is on. Pulling the top left fuse from the fuse box by the steering wheel stops this drain (see my posts on the “Flat Battery“ thread).

The circuit seems to operate the interior lights, radio, blinds and the central locking. However, with the ignition “on” the lights, blinds and radio work again (I didn’t check the central locking). So I’m assuming there is some sort of split circuit going on here. Confusing for us distinctly amateur sparkies trying to remember our ‘o’ level physics!

The central locking is chief suspect (at present) for the current drain as, in our short period of ownership, we’ve had a few problems with the system, ie locking the doors with the key works until the key is pulled out, when they all pop open again. And then it takes a few attempts to get the remote to lock the doors.
With the central locking circuit fuse pulled the remote works fine (obviously only on the drivers door), but I still can’t lock the door with the key if the remote is in “open”. With the remote in “locked” we can open and lock the drivers door with the key.
Should the manual use of the key not override the remote?

My task for this weekend, is to isolate the current drain and to have the central locking working again.

I was hoping that the remote system was the culprit for the current drain, but as it appears to work off a different circuit (ie not the one with the fuse pulled) I’m going to have to check elsewhere.

So my question (at last!) is, how do I isolate the central locking from the radio, blinds etc that all share the same circuit from the fuse?
An obvious place to disconnect would be within the door (I’d be sure I’d got the right wire) but wont this be too far along the circuit to trace a short in, say, the door hinge area (a common place for faults)?

Apologies for my rambling, and thanks in advance for any insights/tips you can give…………

Paul
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dandywarhol
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Re: Central locking circuit leak

Post by dandywarhol » Wed Oct 15, 2008 5:23 pm

Don't know about the central locking wiring Paul but a 0.05A drain could be from the strip light circuit - they've been known to draw more than that. Remove the tube and see if that sorts it
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teenmal
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Re: Central locking circuit leak

Post by teenmal » Wed Oct 15, 2008 5:43 pm

spout wrote:From what I’ve read on this forum and the fact sheets I’m assuming that our Bongo has factory fitted central locking and the “remote” has been added at a later date (the key fob certainly looks after market).

I am trying to trace a 0.05A drain through the circuit that the central locking is on. Pulling the top left fuse from the fuse box by the steering wheel stops this drain (see my posts on the “Flat Battery“ thread).

The circuit seems to operate the interior lights, radio, blinds and the central locking. However, with the ignition “on” the lights, blinds and radio work again (I didn’t check the central locking). So I’m assuming there is some sort of split circuit going on here. Confusing for us distinctly amateur sparkies trying to remember our ‘o’ level physics!

The central locking is chief suspect (at present) for the current drain as, in our short period of ownership, we’ve had a few problems with the system, ie locking the doors with the key works until the key is pulled out, when they all pop open again. And then it takes a few attempts to get the remote to lock the doors.
With the central locking circuit fuse pulled the remote works fine (obviously only on the drivers door), but I still can’t lock the door with the key if the remote is in “open”. With the remote in “locked” we can open and lock the drivers door with the key.
Should the manual use of the key not override the remote?

My task for this weekend, is to isolate the current drain and to have the central locking working again.

I was hoping that the remote system was the culprit for the current drain, but as it appears to work off a different circuit (ie not the one with the fuse pulled) I’m going to have to check elsewhere.

So my question (at last!) is, how do I isolate the central locking from the radio, blinds etc that all share the same circuit from the fuse?
An obvious place to disconnect would be within the door (I’d be sure I’d got the right wire) but wont this be too far along the circuit to trace a short in, say, the door hinge area (a common place for faults)?

Apologies for my rambling, and thanks in advance for any insights/tips you can give…………

Paul
Hi Paul,have a look at fact sheet (fuse box)

No 1 cabin
No 8 cig lighter/mirrors/radio
No 6&7 blinds
No 4 central locking
As Dandy says look at interior light(tube)

Cheers mal..
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Re: Central locking circuit leak

Post by jaylee » Thu Oct 16, 2008 8:00 pm

Just a thought.. Could it be a fault with the actuator? :-k

I have remote locking, but it locks or unlocks when i arm or disarm the alarm..
It drives an actuator in the drivers door that pushes/pulls a rod, which in turn drives the factory fitted CL on the other doors..
I can still lock manually with the key.
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Re: Central locking circuit leak

Post by Skydiver » Thu Oct 16, 2008 10:21 pm

As Im an aircraft electrician we get all manner of snags popping up, the main culprits most of the time is the earths for the circuits if they become dirty, corroded or wet then they will start to cause strange things to happen in a circuit. So I would suggest checking all the earths for the particular ccts, that is if you can find them. hope this helps.
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Re: Central locking circuit leak

Post by bigdaddycain » Fri Oct 17, 2008 10:18 am

Jaylee may be onto something there...The driver's door motor is the "master" motor, if the actuator is sticking,and the other locks operate ahead of the master motor, then the central locking may be defaulting back to "unlock" mode,as it gets confused as to what's going on because the actuators are out of sync... Just a thought, i'd be inclined to try some contact cleaner on the actuator mechanism,then take it from there... :wink:
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spout

Re: Central locking circuit leak

Post by spout » Sat Oct 18, 2008 4:37 pm

Thanks for the replies.

I eventually traced the 0.05A to the radio - even when switched off. Unplugged at the back and then no current drain =D> .
Lots of connectors behind the radio to explore, but I then blew a fuse by poking my multimeter where I obviously shoudn't [-X Think I'll leave the rest to someone who knows what they're doing :roll:

Good news is the remote and central locking are now working fine. Perhaps the dodgy operating was just a sign of a weak battery?

Thanks again.

Paul
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Re: Central locking circuit leak

Post by teenmal » Sun Oct 19, 2008 9:52 am

Hi Spout,glad you found something.
(Most radios have a constant live feed to them,this is for the preset station memory.)

Cheers Mal..
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