No Modem Firmware but has IMEI
Customer came in with the problem that her phone didn’t turn on. I used a PSU and it jumped straight to 250ma after booting and stayed there. No logo or anything. Checked the battery connector voltage and it was only 0.5V. I changed the Tristar and Charging IC and the phone booted normally and didn’t show any sign of power leakage.
When I put the phone back together I saw that it was on searching instead of no SIM. That was for me the indication that something is wrong with the baseband.
I measured the surrounding capacitors and there was no shortage. Replaced the BBPMU and Crystal. Also reballed the Baseband chip. Powered on the phone and measured the capacitors and VCC main for voltage. VCC main has 4.2V and the rest is 0V
Could she have blown here baseband chip when she short her phone?
*#06# shows no IMEI, but when you look in settings/info it shows the IMEI but no modem firmware.
Anyone has encountered this problem before?
Esta é uma boa pergunta?