One IQ Routes - Green Light on but nothing

[pb1966]

TomTom One IQ Routes

Hi

Have the above TomTom which from looking on the internet has the 'green light of death'

I have opened it up via the 2 Torx screws and removed the screen and removed the PCB. Have found one component burned out with some associated local scorching.
There doesn't appear to be any other damaged areas

I would like to have a go at a repair but have no idea where to source a cct diagram to understand which parts are u/s. I understand from a little research that commonly the power control chip goes as does a Zener diode. I suspect that this has suffered an overvoltage.

Can anyone help with info. Have included 2 photos of burned out component.

Best regards

Paul

 

[canderson]

Unfortunately, nobody ever seems to be able to turn up schematics for a TomTom unit. We usually wind up discovering original component numbers/values through 'tribal knowledge' here -- someone who has already opened up a unit for other reasons. Hopefully, someone can tell you what they see on that component.

Meanwhile, if it's the part I think it is (the zener that you suspect), I'd take a VERY long look at your car charger. For reasons I've never been able to fathom, they're using what's known as a 'remote sense' wire on many of the car charger / TomTom units (wire breaks internally), it seems the charger delivers a whole lot more than 5V to the unit. The zener does its intended job briefly, but can't cope with the current at +12 and toasts. So before I'd even replace the component, I'd consider finding another car charger as well. I assume your unit died while attached to the car charger?

 

[pb1966]

Tomtom One IQ Routes

Thanks Canderson

Yes I binned the original charger and bought a new one but unfortunately it was like bolting the stable door after the horse had bolted. The old one had already fried the unit.

Do you think that component is the Zener diode?

Thanks for your input

Regards

Paul

 

[canderson]

More than likely, yes. It is of the right size and shape. If I were dead sure of the orientation, I'd suggest trying the same 5.6V one as we find on other units, but can't tell from your photo what the polarity was supposed to be. You'd have to ohm the actual circuit out to sort out which end was which... unless some kind soul with a ONE will pop up with a photo of the untoasted version.

That said ... I have heard that the ONE also calls this D5 as it does on other models. If so, there's some chance that it's not a zener at all, but a pretty vanilla 1N400X type diode.

 

[yahnsolo]

Hi, this post is quite old now but, here it is... I dont know if you still have your device but in your picture, this is not a Zener diode but a tantalum capacitor that exploded. It's 330µf/10-16v . You can try to change it, with the same value or at least 100µf to 470µf. The positive is close to the small 8 pin chip (speaker amp)

Regards