The next step that the technician should take after replacing the battery in the phone is to check the device for malware. Malware is a malicious software that can infect the phone and cause various problems, such as overheating, battery drain, data theft, pop-up ads, or performance slowdowns. Malware can enter the phone through various sources, such as downloading apps from untrusted sources, clicking on suspicious links or attachments, or connecting to insecure Wi-Fi networks.

To check the device for malware, the technician can use a reputable antivirus or anti-malware app, such as the ones found in the web search results123. The technician can follow these steps:

Download and install the antivirus or anti-malware app from a trusted source, such as the Google Play Store or the Apple App Store.

Launch the app and grant it the necessary permissions to scan the device.

Run a full scan of the device and wait for the results.

If the app detects any malware, follow the app’s instructions to remove or quarantine it.

Restart the device and check if the overheating and battery drain issues are resolved.

Other steps, such as checking the device for updates, checking the device for liquid damage, or checking the device’s charging adapter, may not be relevant or effective for solving the overheating and battery drain issues caused by malware. Checking the device for updates may improve the security and performance of the device, but it may not remove the existing malware. Checking the device for liquid damage may reveal physical damage to the device, but it may not explain the constant overheating and battery drain. Checking the device’s charging adapter may ensure the proper charging of the device, but it may not affect the device’s temperature or battery life when it is not plugged in.