I always told my wife if her hardtop/convertible ever stopped working, I was going to run away from home! Three roof pieces and the trunk bonnet mechanism all moving with eight hydraulic actuators to stow the roof in the trunk and then back up again plus a complicated locking mechanism with cables, micro switches, etc.
Well, it happened last weekend; stopped half way deployed with a message saying "roof movement impaired". Ugh...but fortunately the car was sitting in our driveway. After she begged me not to run away from home, I got my new code reader and found the convertible top module had a code "A691 Hallsensor VSW5.2" Turns out that is the sensor on top of one of the bonnet rams that senses when the ram is fully extended. Only $42 at my local BMW dealer so not bad to buy. Putting it in was kind of a pain since you have to snip a number of zip-ties and re-tie them as you route about 3 feet of wire from the sensor. Plus the removal of a bunch of trunk trim to get to the wire routing. But all is well now and the top is working again.
The question I have though is the hydraulic fluid to use if I ever need to add any to the convertible pump? I know BMW sells their own convertible top oil but I have some Pentosin CHF 11S... anybody know if that fluid would be a good choice or is the BMW fluid mandatory?
2013 328i Convertible Top repair
- Thread starter Scout1
- Start date
JHZR2
Staff member
Good to know it's diy. Ive always been curious of the same - what's the right stuff, and when/how do you replace it?
In a way I kind of wish my 135i top was all mechanical...
Kestas
Staff member
I had the opportunity to buy a convertible BMW. Once I saw how the top operates, I ran away.
Pentosin CHI 11S is used in Mercedes hydraulic top mechanisms.
Well, I know it's a "lifetime" fluid but it's only a matter of time before some leaks out an actuator seal or a hose fitting so I figure I better get an idea on how to top it up and with what fluid!
When I was in college, a friend had a little Honda convertible that was mechanical. Popped a handle and it fell backwards and just picked it up when it was time to close. Now THAT'S reliability! Unfortunately, the roof on my wife's 328i is made out of steel and quite heavy. I had to manually lift the bonnet to get to the sensor I replaced and even though it was on hinges, it was fairly heavy to lift up.
Originally Posted by Scout1
Well, I know it's a "lifetime" fluid but it's only a matter of time before some leaks out an actuator seal or a hose fitting so I figure I better get an idea on how to top it up and with what fluid!
When I was in college, a friend had a little Honda convertible that was mechanical. Popped a handle and it fell backwards and just picked it up when it was time to close. Now THAT'S reliability! Unfortunately, the roof on my wife's 328i is made out of steel and quite heavy. I had to manually lift the bonnet to get to the sensor I replaced and even though it was on hinges, it was fairly heavy to lift up.
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CHF 11S is approved for the top, theyve used that since the early 90s. CHF 202 is also an approved replacement fluid.
Originally Posted by user52165
[quote=Scout1]
Hydraulic fluid on a recent model convertible? I thought they dumped that years ago. Last conv I had was 73 Pontiac 455 Grand Ville with the great GM "Scissors top". Very refined all electro mechanical system that never failed. Have a friend with a 330i conv. about 2010.She is older and rarely drives now.. Same system as yours?
Originally Posted by user52165
[quote=Scout1]
You got very lucky. $42 part and in stock. Kudos on fixing it yourself.
It's hydraulic oil in a closed system that sees very little use. Unless you're OCD about changing the fluid in your floor jacks as well, I wouldn't bother unless it's leaking. The convertible top on my Mustang takes ATF, and Ford says you don't need to change it. I don't see why I would need to, either.
At least you didn't have to replace the entire top like I did, turns out that's a fair bit of work!
