Help to identify burnt component with illegible specification

Thread Starter

rmpx

Joined Dec 22, 2021
8
Hello everyone!

I ask for the humble help of those who know how to identify the name of the component in the attached photo.

It's mostly burnt out I can't read the spec! I didn't find any scheme on the Internet. Does anyone know if it is a ceramic capacitor, varistor, thermistor?

This burned-out component is from the electric window regulator of a car (PT Cruiser 2008 - Chrysler - front left door [driver]).
 

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dl324

Joined Mar 30, 2015
14,305
Welcome to AAC!
Does anyone know if it is a ceramic capacitor, varistor, thermistor?
The picture doesn't give much to go on. It's unlikely to be a capacitor, might be a MOV. If it's a MOV and it failed open circuit, the circuit might still work. It just won't have any over voltage protection. If it's a MOV, you need to investigate what could have caused the surge.
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
Hello MrChips!

It's not that simple for me, in my country there are few models of this car, and it will be almost impossible to find a club of people that deal specifically with this.

Hello dl324!

I thought it could also be a varistor, but it's still just a guess. It would still lack details of resistance in relation to voltage... I have no idea which one could put in place... And investigating what might have caused it, in a vehicle, is a Herculean task...

How do you electronics pros often identify unreadable burnt components when there's no schematic? Do you think it's more reasonable to be a ceramic capacitor to prevent noise or a varistor to prevent an overvoltage?

I don't know if it helps: when I add voltage to the electric motor, it works, but when I have to use more force, like lifting the window, it just stops working and doesn't come back until I remove the cable, cut the current completely, and connect again.

Could anyone give any more guesses?
 

dl324

Joined Mar 30, 2015
14,305
How do you electronics pros often identify unreadable burnt components when there's no schematic?
We trace the circuit and make a schematic. Knowing how the unidentifiable component is wired lets us make some intelligent guesses.
Do you think it's more reasonable to be a ceramic capacitor to prevent noise or a varistor to prevent an overvoltage?
In conservative, well designed circuits, ceramic capacitors shouldn't be used in a way that their maximum ratings can be exceeded.
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
Thank you dl324,

The scheme, in this case, is very simple. This burnt component is connected in parallel with the poles of the electric motor (12V-DC). Is it possible to make any assumptions? The electric motor is 12v, and unfortunately, I don't have information about its power.

Forgive my low IQ, but I didn't understand your answer to a second question. Is it a conclusion by the burnt component or an obvious exclusion from the first hypothesis? You mean it would be a varistor?

It would help me a lot if I knew which component is usually connected in parallel with high torque electric motors and for what function it is used (current stabilization, avoid peaks...)
 

dl324

Joined Mar 30, 2015
14,305
This burnt component is connected in parallel with the poles of the electric motor
That would eliminate it being a surge limiter (NTC resistor) or PTC fuse.
Is it a conclusion by the burnt component or an obvious exclusion from the first hypothesis?
Ceramic capacitors don't normally fail unless they're stressed electrically or mechanically.
It would help me a lot if I knew which component is usually connected in parallel with high torque electric motors and for what function it is used (current stabilization, avoid peaks...)
The most typical component would be a back EMF suppression diode on a DC motor and an RC network on an AC motor. Those would typically be included as part of the motor driver circuit. You're saying that this appears to be part of the motor assembly?
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
dl324,

Thank you very much, that's just what I needed, intelligently limiting hypotheses.

Yes, this component is mounted together with the engine. It is not a separate component from the engine, it was assembled with it. Sorry if I wasn't clear on that.

This burnt component, I don't know the cause of the burn, but the short extended from the control module (windows activation buttons) to this component (window regulator). I didn't find other spots with short signals (burned out). But in general, the current is flowing and turns the motor on from time to time. Sometimes the regulator works normal, sometimes it looks dead.

For me to be able to eliminate the electric motor, I would need to find out what this component is, if it is just to prevent a spike or if it is essential for the correct functioning of the motor. At this moment, the engine runs randomly.
 

MrChips

Joined Oct 2, 2009
25,919
If it is across the terminals of the motor then it is there for noise suppression.
The motor should still run with the blown component removed. It is probably a capacitor.
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
Thank you all!

One more thing: can I try to replace it with an electrolytic capacitor? I don't know the voltage or the capacitance, would it be wrong to put a 16v and 1000uF? I know it's a long shot, but if you guys say it won't blow it all up, I think it's worth a try:p
 

MrChips

Joined Oct 2, 2009
25,919
Thank you all!

One more thing: can I try to replace it with an electrolytic capacitor? I don't know the voltage or the capacitance, would it be wrong to put a 16v and 1000uF? I know it's a long shot, but if you guys say it won't blow it all up, I think it's worth a try:p
No. Don't put an electrolytic capacitor.
Replace it with a 100nF capacitor. Voltage is not critical, 50V or higher will do.

If the motor is not already working then the capacitor will not change anything.
 

dl324

Joined Mar 30, 2015
14,305
can I try to replace it with an electrolytic capacitor? I don't know the voltage or the capacitance, would it be wrong to put a 16v and 1000uF?
If the motor is reversable, you can't use a polarized cap. A cap in the package you showed couldn't possibly be 1000uF.
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
MrChips,

Is this capacitor you recommended usable in case of reversable dc motor? Just to be sure, based on Mr. dl324's observation.
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
Yes, I'll be back to tell you if it worked. Please, I changed my last answer, could you confirm me if your recommendation would work for dc reversible engine?
 

Thread Starter

rmpx

Joined Dec 22, 2021
8
I just saw that a ceramic capacitor has no polarity. Forgive my ignorance :eek:
Now yes, happy Christmas and God bless you all.

I will be back to give the results!
 
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