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Fanfold Paper
Posts: 3
Location: Nashville, TN USA
Views: 2,222
Message 1 of 3

E420 Thermal Sensing Error

I bought two E420s on the same  day last fall. One works flawlessly. The other has had issues from day one with hanging on startup. Usually it would take three or four attempts to get it started through safe  mode. Now, a "Thermal Sensing Error" message sometimes appears on startup. I restored it to "factory" condition and  I've updated the bios and all drivers. But the problem persists. Any guidance will be appreciated.

Retired Partner
Posts: 955
Location: INDIA
Views: 2,184
Message 2 of 3

Re: E420 Thermal Sensing Error

It is really sad to know that you have issue since you purchased the laptop.


As you have already updated the BIOS and reload the Operating System also.


The issue seems to be with CPU fan (heat sink). I would suggest you to contact the support center if the laptop is in warranty so the service can be done.

Country or RegionLanguageTelephone numberHours of operation
United States English 1-800-426-7378 
Select "Option #1"
24 hours/day
7 days/week



Best Regards,


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Fanfold Paper
Posts: 3
Location: Nashville, TN USA
Views: 2,113
Message 3 of 3

Re: E420 Thermal Sensing Error

I have now returned this unit three times for repair. Each time it comes back, it works OK for a few hours, then it locks up. On restart the "thermal sensor error" reappears and it takes several attempts to get it to re-boot. The last service tech assured me on the phone that they had run a lengthy test and they unit has no problems. Unfortunately, it does have a serious problem. Who can I contact about a replacement unit as this machine has been faulty since day one?

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