AFT Roof won't go up.

[mrsam]

You're quite right each motor pushes the 2 flexable drives.
At the end of each motor,which have brushes and are these probably cause the motor failures,is a worm drive.This turns a plastic gear.The gear is conected to the output drive via a friction plate.The ouput drive has a gear sitting in a chanel and the two flexable drive cables sit on either side of the gear.When the motor turns one flexable cable moves one way the other moves in the opposite direction , passes behind the motor, crosses the back of the roof and then travels via the other motor and pushes the roof in the same direction as the first motor. The friction drives probably compensates for one motor being siezed up.The twisting of the roof carriers probably occures when a flexable cable come out of its guides and only one side is pushed.

[Dodgey]

Thanks.

We had a little test on Thursday. It didn't make much sense, on the 4 pin plug.

Unplugged, none of the pins have any voltage across them, in any combo.
Plugged in, nothing.
Unplugged with with the engine running: nothing.
Plugged in with the engine running: 13v across Blue and Green, and Red and Green. Black didn't show anything.
Now with the roof button pressed, engine running, plugged in : same as above but 8Volts instead of 13v.


I tried pushing 12v straight into green / red / blue - nothing on two of them and the third (can't remember which colour - green I think) made the dashboard light up That was just a pure live - leaving the earth out - I didn't want to risk that without knowing the exact pinouts.

[g8dhe]

The 4 Pin plug;
1A - Earth - Black
1B - Motor - Blue
1C - +12v fused at 30 Amps - Green
1D - Motor - Red

I would check the fuse first, especially as you say there is no power present;


By linking on the socket (A to B and C to D OR A to D and B to C) you should be able to drive the motor in either direction

[g8dhe]

Just noticed the latter tests where you say power is present but falls from 13 volts to 8 volts, either the motors are stalled or your getting a voltage drop in the system, I would still check the fuse and clean the contacts as a first step, and then perhaps measure the current being drawn, at the fuse, if its in the order of 5-10 Amps then it would suggest a stalled motor, if its less then that then probably a voltage drop due to a poor connection or possibly a damaged relay in the module, whilst replacing the relay is a simple job obtaining the specific one could be a problem as its two relays in bridge format in the same package - the details are in the diagram above by clicking the Orange box, but I doubt that it is the relay (linking the socket would prove the case, eliminating the relay) my bet would be on stalled motors.

[Doone]

If the roof/motor is jammed, you can get the roof up far enough to remove the motors. It's tricky but Allan has done it a few times, without breaking the roof. I've copied these instructions from Allan's website:

Roof jammed and the usual fixes haven't worked? If the roof motors will not operate, the roof can be raised manually at the rear, to access the motors.

There are two roof motors on the Mazda Bongo AFT. One is located at each rear corner of the roof.

Undo the rear hinges, you'll need a long socket to do this. Start to lever the roof up gradually, in the centre, with a tyre lever or similar. Keep the roof level as you do this. Wedge it up as you go. Raise it enough to get access to the two black covers that are over the motors. The covers pull off - remove them.

The motors are secured in place with either allen keys or screws. (Because of the limited space, the allen key type are easier to access.) Undo the two motors, they'll fall off and dangle by their wires, so don't drop them.

(If you flick the roof switch, the motors may now work. But don't raise the roof until the motors and the rear hinges are back in place.)

If the motors don't work, you now have them accessible for testing/repair/replacement. Putting them back into place is tricky due to the limited access, but it can be done.

[spen68]

If the roof/motor is jammed, you can get the roof up far enough to remove the motors. It's tricky but Allan has done it a few times, without breaking the roof. I've copied these instructions from Allan's website:

Roof jammed and the usual fixes haven't worked? If the roof motors will not operate, the roof can be raised manually at the rear, to access the motors.

There are two roof motors on the Mazda Bongo AFT. One is located at each rear corner of the roof.

Undo the rear hinges, you'll need a long socket to do this. Start to lever the roof up gradually, in the centre, with a tyre lever or similar. Keep the roof level as you do this. Wedge it up as you go. Raise it enough to get access to the two black covers that are over the motors. The covers pull off - remove them.

The motors are secured in place with either allen keys or screws. (Because of the limited space, the allen key type are easier to access.) Undo the two motors, they'll fall off and dangle by their wires, so don't drop them.

(If you flick the roof switch, the motors may now work. But don't raise the roof until the motors and the rear hinges are back in place.)

If the motors don't work, you now have them accessible for testing/repair/replacement. Putting them back into place is tricky due to the limited access, but it can be done.

Thanks Doone.. The bus is booked in to go and see Bell Hill in Norton St Philip on Saturday. I spoke to the guy there earlier, literally just after I'd read your post and he sounded a bit sceptical about the whole idea. He thinks there's a good chance it'll be something simple but if not it was better to cut the motors out and replace the lid! I'll show him the post when I'm up there and see if he changes his mind.

Cheers, Spencer

[twidds]

Is it sorted and if so how