# Actuator Broken But Motor Works **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** mercedes-benz, e-class\ **Created:** [June 24, 2022, 6:40pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854 "2022-06-24T18:40:59Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 6:40pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/1 "2022-06-24T18:40:59Z")
Ok so the actuator for the front driver side wasn’t working so I’ve removed the main housing and also took it apart and eventually ended up with the motor itself. To make sure, I directly connected the motor to a 12V DC power supply and it WORKED. Every other part looks fairly clean and sturdy so please tell me that I don’t have to rummage around for a broken connection and it could still be the motor. Thanks in advance. ---
**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\ **Post date:** [June 24, 2022, 7:06pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/2 "2022-06-24T19:06:54Z")
You can get an inexpensive multimeter (~$20) to help with the rummaging. I might be more specific if you share with us what this motor is actuating. ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 7:11pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/3 "2022-06-24T19:11:34Z")
Door lock actuator ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [June 24, 2022, 8:13pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/4 "2022-06-24T20:13:43Z")
Is it not working when you press the door lock switch? If that is the case, it might be the switch itself ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 8:19pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/5 "2022-06-24T20:19:29Z")
It is a central locking system so there is a switch that locks all four doors. When pressed all the other doors gets locked but this one. I shook around the main wiring harness but didn’t seem to have any effect. I guess i should look into the wiring harness for the actuator itself. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [June 24, 2022, 8:26pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/6 "2022-06-24T20:26:35Z")
Since the actuator works ok when you connect 12 volts to it, the next step is to measure what voltage is connected when you do it the normal way, pressing the door lock switch. Do you have a portable volt-meter? ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [June 24, 2022, 8:29pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/7 "2022-06-24T20:29:57Z")
check for a broken wire in between the fender and the door. there will be a bunch of wires in a rubber case. you can usually pull back the rubber part to see the wires inside. ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 8:30pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/8 "2022-06-24T20:30:40Z")
I have but what should i do after measuring the said voltage ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 8:32pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/9 "2022-06-24T20:32:10Z")
I did but will try again ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [June 24, 2022, 8:47pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/10 "2022-06-24T20:47:15Z")
> [@emayar88\_177321](#): > > I have but what should i do after measuring the said voltage What was the measurement? How many volts? ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 8:49pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/11 "2022-06-24T20:49:31Z")
Sorry, I meant I have a multimeter and what should I do after the measurement ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [June 24, 2022, 8:53pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/12 "2022-06-24T20:53:01Z")
> [@emayar88\_177321](#): > > hat should I do after the measurement Post it here ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 24, 2022, 9:10pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/13 "2022-06-24T21:10:43Z")
Alright thanks guys I will be updating. ---
**Author:** ![emayar88\_177321](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@emayar88\_177321](https://community.cartalk.com/u/emayar88_177321)\ **Post date:** [June 25, 2022, 12:26pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/14 "2022-06-25T12:26:01Z")
There is 12 V coming to the actuator. But i’ve realised that the motor turns when removed from the actuator housing but can’t turn the gears when assembled. I am back to thinking it is the motor now so ordered a replacement. It is cheap even if it doesn’t fix the problem. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [June 27, 2022, 10:56pm UTC](https://community.cartalk.com/t/actuator-broken-but-motor-works/184854/15 "2022-06-27T22:56:26Z")
If a new actuator doesn’t do the trick, try lubing the entire chain of connections from the actuator to the door lock mechanism. On my cars I use a spray version of white lithium grease. Focus on the door lock end of the chain, that part is more exposed to the weather. Look for something broken or loose too.