Auto WLtoys 12428 Steering Issue: Replacing CF 502 Potentiometer, Car Turns One Way Only

Hello,
some time ago my son broke the steering wheel for this model. After unscrewing the remote control, it turned out that you need to modify the element responsible for twisting. The potentiometer marked CF 502 was originally mounted, as in the pictures below:

The potentiometer could not be connected to the control element (steering wheel), so I decided to replace it with others. In the electronics store, a 5 k? potentiometer was chosen, exactly like here:

After connecting for a few minutes, the twist worked like new, then getting weaker. After charging the car battery, it turned out that the car turns only one way, the other as if it was blocking something. We manage halfway in such a way that I switch to the regulation which is responsible for setting the wheels for straight travel, so that it turns equally left and right, but this is at the expense of the turning radius.

What is wrong ? How to fix it ?

CF 502 potentiometer with 5 k? linear potentiometer, but with a working range of, for example, 110 degrees, 45-240 degrees, depending on the manufacturer, there must be a potentiometer from modeling apparatus.



After the embankment you can see the scope of the field of activity.
-----------
to check.
Fixed position "0" on the potentiometer not set.
And the servo incorrectly positioned lever point "0".


.

That would match, it looked original.


What should the replacement be then? Alternatively, where to buy?
I visited three electronics stores and one model shop and they didn't have anything like the original.

Quote:

Fixed position "0" on the potentiometer not set.
And the servo incorrectly positioned lever point "0".

I understand that after installing the appropriate potentiometer will be set to "0" on the potentiometer, i.e.


and possibly (although there was nothing buried here) servos in the model.
Yes ?

The zero on the potentiometer is factory set in the form of a projection acting as the basis for its arrangement in the apparatus. And the cut needed to maintain the position of the steering wheel or throttle lever.
When you turn on the model and apparatus, the servo should assume the zero position, then the lever position should be set. To get the same steering angle and to adjust the length of the pull rod so that the wheels are set for straight travel, all that is left is to slightly adjust the trimmer.
On the pattern that fell, you would have to search ebay or translate from another,
or buying similar dimensions and axis for adaptation.
I stock up on AliExpress - CF B502 potentiometer.
Or - B5K 5K Linear Taper Potentiometer for RC Transmitter Control 120 Degree Rotation



But first you need to set the range of the potentiometer in degrees.

link

yarkk wrote:

it looked original.

Careless soldering of the short circuit.

.

1 PAWEL wrote:

But first you need to set the range of the potentiometer in degrees.

The working range of the steering wheel is limited as shown in the figure below, i.e. 40 ° to the left and 40 ° to the right.

If the range of the potentiometer is those silver lines on the potentiometer, it goes out on the left and right together about 180 °, but it is difficult to accurately measure.

What should the potentiometer be like?
I didn't buy anything on ebay or aliexpress. There is nothing in PL?
Alternatively, I can transfer the indicated amount to your account if you have such an item.

1 PAWEL wrote:

Careless soldering of the short circuit.

I solder as often as I weld - as needed so please don't point out

I will search the internet and see what I find.

Probably - Wltoys Potentiometer with wire plug

https://pl.aliexpress.com/item/4pcs-B502-B5K-...le/32641944854.html?spm=a2g17.search0304.4.47. MwguOi

https://www.aliexpress.com/w/wholesale-b5k-degree.html

https://pl.aliexpress.com/item/Wltoys-Q333-RC...er-Connecting-line/32749460825.html?spm=a2g17. search0104.3.2.ThC92U & ws_ab_test = searchweb0_0, searchweb201602_1_10152_10065_10151_10068_10344_10342_10343_10340_10341_10304_10307_10301_10137_10060_10155_10154_10056_10055_10054_10059_100031_10099_10338_10339_10103_10102_440_10052_10053_10142_10107_10050_10051_10171_10326_10084_10083_10080_10082_10081_10110_10111_10112_10113_10114_143_10312_10313_10314_10078_10079_10073, searchweb201603_11, ppcSwitch_5 & btsid = 2b40c48f-d304-499b-8039-210499eb76e5 & algo_expid = a923f12f-be1b-4e0b-acbd-db69ffb72802-0 & algo_pvid = a923f12f-be1b-4e0b-acbd-db69ffb72802?

The one from the first link has exactly the same mark, but if you compare the pictures, it has a slightly different scope of work.


So the original work range should be less than 60 °?
Maybe 45 ° - in the first post you pasted a photo of this, but with a different marking.

I can even buy a few models and try, but am I going in the right direction?

The one from the first photo is the entire range is 120 degrees, and yours is 90 degrees.
You can try to install this B502 60 °.
B5K-45 ° are not available.
http://www.rctrax.pl/potencjometr-gazu-do-aparatury-gfsk-i-hk-gt3b/2107/

Link B502 50 °
link

This one is the closest in appearance, the 50 ° range seems to be very close. However, you need to demolish this module to separate the potentiometer - and here I am a little afraid that I will not find anything to control this potentiometer.

B502 60 ° probably will be the best of them. If you have one for sale, I will gladly buy it back.

Could this have a maximum working range of 30 ° one way?
B5K 30 °

Unfortunately I only have 120 °.
This is not with a 30 ° range, only axis position data.

And can removing this embankment reduce the range?

yarkk wrote:

And can removing this embankment reduce the range?

It won't help, this embankment is not of equal value. Just like a regular potentiometer, it works within a certain range.
I guess it remains testing with similar parameters of potentiometers
or https://www.aliexpress.com/item/Wltoys-12428-...4.56010108.5.9.Xsxvfh&&scm=1007.12783.72505.0 - PLN 42

I also thought about this transmitter, it differs in that there is no potentiometer from the "gas" control and it is for 3 batteries and not for 4.

Do you have this 120 ° for sale?
If so, send data to pw.

yarkk wrote:

And do you have this 120 ° for sale

No, because I only have one spare.
The gas adjustment potentiometer is a trimmer that reduces speed or sets to max speed.

link