Squiffy
Forum Member
We've just returned from a 5 week trip to Portugal (Caught up in the fires there near Porto, but that's another story). We started off in Dieppe called into see my Brother and his wife in Brittany then continued on down past Biarritz and on through Spain to North Portugal and on down. Have to say Portugal was lovely and incredibly cheap compared to France and Spain. However I digress, after a great three weeks travelling from one site to another we packed up camp and started the van up ready to continue on, the step buzzer did it's usual buzz till the step fully retracted and off we went to the next destination.
Having arrived the wife as per usual pressed the step down button and the step refused to slide out, after much ado about checking this fuse and that fuse plus the relay and associated wiring, it's been almost eleven years since I fitted the step and had to rack the old grey matter on how I'd wired it up, I came to the conclusion that the step had jammed up in some way because I could here a faint click from the step when the button was pressed but no visible effort at all from the step. As we had only a week or so left of our holiday I decided not to muck around with it and to leave fixing it when we got home.
Once we were home the fix was quite simple, but could have been very costly if I had not discovered a certain fact.
The front plate comes off by removing the two plastic end caps which are attached by two tiny screws screwed into the back of the end caps, these can then be removed which inturn show 4 larger self tappers two on either side holding the front plate on. Once the front plate is removed this allows the bottom plastic weather cover to be slid out from under revealing the mechanics of the step and motor housing.
On inspection I realised that the step and the actuation arms were perfectly OK so the main problem was evidently with the motor or gearboxes. This now meant that to continue with the repair it entailed the complete removal of the step, which was comparatively easy as its only held up with four nuts the problem was really the wiring as that disappeared up into the interior of the van and I could not remember where I had joined (Extended) the wires as they went through a fixed conduit to the other side of the van, so the best solution was to snip all four wires giving enough lenght to resolder them later.
Having removed the step it became an easy self evident job to remove the step from the actuator arms and slide the step out and then remove some 8 or ten self tappers which held the motor and gearboxes to the step housing. Having got the motor and gearbox housing off this left two large gears still mounted on the step panel it was here that the problem started to show itself.
One of these gears was fairly easy to pull out of its bearing but the other was stuck solid and would not budge or even turn, I had to use some gentle heat very sparingly as the bearing and the gears are made of some sort of aluminium alloy. Once removed it showed that the bearing had sized up due to corrosion and lack of lubrication.
I then turned to the motor, the gear box housings house the two pinion gears one each side attached by a square shaft going through the motor gearbox which is attached by a very small circlip on each end of the shaft which in turn holds the pinion gears from sliding off the shaft. I managed to snap the one trying to get it off
however I was now able to remove the shaft from the gearbox mounting and remove the shaft from the motor, leaving the motor and it's gearbox free to be inspected.
My first test was to apply 12volts to the motor terminal at which point I got the familiar click and the same click when I reversed the voltage. So I the removed the gearbox from the motor which left me with the motor and worm drive on the motor shaft, this would not turn when I tried to turn the motor so something was obviously wrong. I then removed the two screws holding the motor front plate from the motor housing and withdrew the motor rotor to find that the brushes and plastic housing had melted into one lump totally siezing the motor, there was no recourse than purchasing a new motor.
Now here is the interesting bit. A new motor from Thule is an eye watering £192, but on looking on Ebay I noticed that others were selling a replacement Thule step motor for £85 pounds, but wait a minute a little further on in the listings were exactly the same Bosh motors listed as headlight beam adjusters for £37 free postage, so I bought one of those the Bosh part number was the same on the one for £85 as the one for £37 so I bought one of those, it arrived next day by DHL perfect.
Lubed everything up with grease in the gearboxesand PFT spray for the actuator arms etc and put it all back together tested on the bench it worked perfectly, so refitted to the van resoldered the wires with those lovely waterproof soldered sleeves using my heat gun and Bob's your Auntie all back and working.
P.s. Some advice if your going to do this.
1) Take photos of every stage in dismantling.
2) Make sure you have the big main gears in the right place when refitting the motor and gearbox housings ( Or you will have a lock up with the actuation arms trying to move in opposite directions).
3) Apparently some versions of this motor use a star drive instead of a square drive. But I've studied the pictures of both and my opinion is that so long as in my case it's the motor that's at fault you can just swap out your star drive motor gearbox with the square drive gearbox. ( The sellers on Ebay are saying if you have the stardrive motor it can only be purchased from Thule).
Pps.
Also can be bought on Amazon
Bosch 0390203266 Servo Motor https://amzn.eu/d/ixQNSbq
Having arrived the wife as per usual pressed the step down button and the step refused to slide out, after much ado about checking this fuse and that fuse plus the relay and associated wiring, it's been almost eleven years since I fitted the step and had to rack the old grey matter on how I'd wired it up, I came to the conclusion that the step had jammed up in some way because I could here a faint click from the step when the button was pressed but no visible effort at all from the step. As we had only a week or so left of our holiday I decided not to muck around with it and to leave fixing it when we got home.
Once we were home the fix was quite simple, but could have been very costly if I had not discovered a certain fact.
The front plate comes off by removing the two plastic end caps which are attached by two tiny screws screwed into the back of the end caps, these can then be removed which inturn show 4 larger self tappers two on either side holding the front plate on. Once the front plate is removed this allows the bottom plastic weather cover to be slid out from under revealing the mechanics of the step and motor housing.
On inspection I realised that the step and the actuation arms were perfectly OK so the main problem was evidently with the motor or gearboxes. This now meant that to continue with the repair it entailed the complete removal of the step, which was comparatively easy as its only held up with four nuts the problem was really the wiring as that disappeared up into the interior of the van and I could not remember where I had joined (Extended) the wires as they went through a fixed conduit to the other side of the van, so the best solution was to snip all four wires giving enough lenght to resolder them later.
Having removed the step it became an easy self evident job to remove the step from the actuator arms and slide the step out and then remove some 8 or ten self tappers which held the motor and gearboxes to the step housing. Having got the motor and gearbox housing off this left two large gears still mounted on the step panel it was here that the problem started to show itself.
One of these gears was fairly easy to pull out of its bearing but the other was stuck solid and would not budge or even turn, I had to use some gentle heat very sparingly as the bearing and the gears are made of some sort of aluminium alloy. Once removed it showed that the bearing had sized up due to corrosion and lack of lubrication.
I then turned to the motor, the gear box housings house the two pinion gears one each side attached by a square shaft going through the motor gearbox which is attached by a very small circlip on each end of the shaft which in turn holds the pinion gears from sliding off the shaft. I managed to snap the one trying to get it off
however I was now able to remove the shaft from the gearbox mounting and remove the shaft from the motor, leaving the motor and it's gearbox free to be inspected.My first test was to apply 12volts to the motor terminal at which point I got the familiar click and the same click when I reversed the voltage. So I the removed the gearbox from the motor which left me with the motor and worm drive on the motor shaft, this would not turn when I tried to turn the motor so something was obviously wrong. I then removed the two screws holding the motor front plate from the motor housing and withdrew the motor rotor to find that the brushes and plastic housing had melted into one lump totally siezing the motor, there was no recourse than purchasing a new motor.
Now here is the interesting bit. A new motor from Thule is an eye watering £192, but on looking on Ebay I noticed that others were selling a replacement Thule step motor for £85 pounds, but wait a minute a little further on in the listings were exactly the same Bosh motors listed as headlight beam adjusters for £37 free postage, so I bought one of those the Bosh part number was the same on the one for £85 as the one for £37 so I bought one of those, it arrived next day by DHL perfect.
Lubed everything up with grease in the gearboxesand PFT spray for the actuator arms etc and put it all back together tested on the bench it worked perfectly, so refitted to the van resoldered the wires with those lovely waterproof soldered sleeves using my heat gun and Bob's your Auntie all back and working.
P.s. Some advice if your going to do this.
1) Take photos of every stage in dismantling.
2) Make sure you have the big main gears in the right place when refitting the motor and gearbox housings ( Or you will have a lock up with the actuation arms trying to move in opposite directions).
3) Apparently some versions of this motor use a star drive instead of a square drive. But I've studied the pictures of both and my opinion is that so long as in my case it's the motor that's at fault you can just swap out your star drive motor gearbox with the square drive gearbox. ( The sellers on Ebay are saying if you have the stardrive motor it can only be purchased from Thule).
Pps.
Also can be bought on Amazon
Bosch 0390203266 Servo Motor https://amzn.eu/d/ixQNSbq
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