w202 delayed parklight and aircon blower function

[jakewise]

Mods, I hope I posted in the right forum, please transfer if it isn't.
I have noticed that since I use the car sparingly, when I turn on the park light, the bulbs for the center panel where the mechanical switches is located for the aircon blower does not light up, and so if you turn on the aircon switch, it will also not turn on. But when car is idled for a long time with the park light switch on, eventually the bulbs in the center console will light up and so the aircon blower will also work. Any ideas what I should do to correct this delayed lighting of the park light at the center console and aircon blower? I presume that the lines may be corroded somehow but I do not know where to start looking.
I tried spraying with contact cleaner the fuses located at the engine compartment but still the same.

 

[LostKiwi]

It sounds like you have a bad connection somewhere. Other than tracing every connection there's no quick way to find it. It may also be a dry joint on the circuit board of the unit.

 

[Blobcat]

As per above sounds like a poor connection (electrical) - I'd have a go at taking the unit our or at least getting to the connectors and moving and re-seating them

 

[jakewise]

LostKiwi and Blobcat, thanks for the reply, well noted

 

[jakewise]

Just to update, I removed the aircon panel and tried spraying contact cleaner to all the electrical teminals and also that with the PCB board and reseated the terminal plug, but problem is still there. It looks like I will have to replace the aircon panel, any suggestions where I can source one?

 

[om613]

Yes, me. I'm breaking one.

 

[jakewise]

What's your aircon panel's part number? Mine is
210 830 31 85

 

[om613]

Tell me where it is, then I might be able to take it out to look at the part number.

 

[jakewise]

Tell me where it is, then I might be able to take it out to look at the part number.

The aircon panel is the switch of the aircon. Mine has the two big rotary switches with three push button switches between them. It is located right below the center aircon vents and above the ashtray.

 

[V6Matty]

May sound daft but what’s the voltage of your battery like, I know it doesn’t sound like a failing one but we all know mercs do strange things with low voltages

 

[jakewise]

May sound daft but what’s the voltage of your battery like, I know it doesn’t sound like a failing one but we all know mercs do strange things with low voltages

I have not really took that into consideration as I don't know how to test it specifically for the aircon panel switch. Nevertheless, the symptoms don't quite show it has a low voltage, otherwise, it surely will affect other electrical components of the car which does not

 

[V6Matty]

True, I’m more thinking it because it all springs into life after a few minutes of idle?

 

[jakewise]

True, I’m more thinking it because it all springs into life after a few minutes of idle?

It used to come on after less than 30 minutes of idle but lately, it takes about an hour before in gets back to life

 

[V6Matty]

Yep, starting to sound like a dry joint really, as I said though worth a shot in checking the battery is in good condition and that the alternator is giving a full charge

 

[jakewise]

Yep, starting to sound like a dry joint really, as I said though worth a shot in checking the battery is in good condition and that the alternator is giving a full charge

Battery I believe is still good as it starts quite well, but thanks for your input.

 

[jakewise]

I'd like to ask for those who have changed their aircon panel, is it just plug and play assuming that it has the same part number? Or do you need a Star diagnostic to reset it?

 

[om613]

No, it won't need Star. I'll see if I can remove mine tomorrow.

 

[jakewise]

No, it won't need Star. I'll see if I can remove mine tomorrow.

Thank you for this information