Technical Weird electrical problem with lights

[Jaka Cvajnar]

i got a weird problem with my low beam lights. every time i turn on rear window heaters my lights get dimmer, also if i use front door electrical window swich it does the same. if i have the rear heaters turned on the lights are dimm all the time, if i use the electrical windows they get dimm untill i stop pressing the button. its not totally dim but it is noticable if i park upfront of someting and do it.

any idea why it does that? battery new , one of the bulbs is also pretty new.

 

[brinker]

What's the charging voltage like? Might be a poor alternator.

 

[Jaka Cvajnar]

to be fair i dont know. shauld i go test it? could a bad alternator really cause this problem?

 

[brinker]

If the charge voltage is low, then you'll have a lower battery voltage as well. So yes, you need to check this

 

[sandaru]

Can this kind of issue and a intermittent eps red light issue caused by bad starter motor if the battery and alternator are fine?

 

[Jaka Cvajnar]

If the charge voltage is low, then you'll have a lower battery voltage as well. So yes, you need to check this

okay ill take the car to a mechanic to check the charging voltage, what kaind of voltage shauld i have? 13.5-14v right?

 

[brinker]

okay ill take the car to a mechanic to check the charging voltage, what kaind of voltage shauld i have? 13.5-14v right?

No you're looking at something closer to 14,3-14,7V

 

[Scudmonkey]

Most cars the lights will dim slightly when heater/windows etc are used. Interior light will also dim a little. Usually when you rev the Engine a little they all brighten up as the Alternator will be producing more power.
As others have said get the electrical system, specifically the alternator checked for Power output.

 

[Jaka Cvajnar]

took the car to get charging voltage tested, it had 14v or something. the mechanic said the alternator working okay. asked him about the problem and he had no thoughts about it unless checking ...

so back again, what could be the problem of the dimmed lights if alternator is ok?

 

[chris3234]

Either detective battery or possibly an earthing issue
Quickest one would but to remove to battery and take it to a place that load tests them most of them usually do it for free

 

[Jaka Cvajnar]

Either detective battery or possibly an earthing issue
Quickest one would but to remove to battery and take it to a place that load tests them most of them usually do it for free

battery is brand new, less than 2 months.

i also thought about earthing but idk how that would cause dimming when using electrics

 

[chris3234]

battery is brand new, less than 2 months.

i also thought about earthing but idk how that would cause dimming when using electrics

High resistance caused by a poor connection can easily cause a voltage drop meaning the lights go dimmer
Start checking and earth connection you can find if any look dirty or corroded remove and clean them with wirewool or something like that

 

[Jaka Cvajnar]

High resistance caused by a poor connection can easily cause a voltage drop meaning the lights go dimmer
Start checking and earth connection you can find if any look dirty or corroded remove and clean them with wirewool or something like that

any idea where i could locate any of the earthings? its mk2b

 

[chris3234]

any idea where i could locate any of the earthings? its mk2b

Don't know the car myself but perhaps this is worth a try
Seem to be discussing earth points for the MK2 Punto

https://www.fiatforum.com/punto-ii/143738-punto-earth-points.html

 

[sandaru]

Can this kind of issue and a intermittent eps red light issue caused by bad starter motor if the battery and alternator are fine?

Hello any idea of bad starter motor?