iPhone 5s does not turn on error 40 - GSM-Forum

karoliens · 06-21-2018, 16:43

Hi guys,

I am a bit stuck as I could not solve the issue. I have an iPhone which is totally dead but is recognized by PC. When I try to recover it through iTunes it gives error 40. When I connect to DCPS and press and hold power button it jumps to ~90mA and stays there.
No short on VCC_MAIN or battery. I also tested TriStar 1v8 and 3v0 lines and it shows 0v. My guess it is either PMIC or NAND.
Do you have aby suggestions?
Thanks in advance.

Amr.OKa · 06-21-2018, 18:01

Error 40 Nand not detected

karoliens · 06-21-2018, 21:02

I know that it is related with NAND but it could be either NAND itself or PMIC. I will try to test NAND power lines. If they are not present then it should be PMIC.

elecsoluces · 06-22-2018, 06:41

Hello,

You should check the PP3V0_NAND line, if it is shorted one of the caps on this line is defective.

karoliens · 06-26-2018, 17:44

Just an update. I have checked PP1V2_NAND_VDDI, PP3V0_NAND, PP1V8 lines and all of them are present therefore I suspect NAND itself. What do you think?

06-21-2018, 16:43	#1 (permalink)
karoliens Junior Member Join Date: Mar 2017 Posts: 14 Member: 2690483 Status: Offline Thanks Meter: 1	iPhone 5s does not turn on error 40 Hi guys, I am a bit stuck as I could not solve the issue. I have an iPhone which is totally dead but is recognized by PC. When I try to recover it through iTunes it gives error 40. When I connect to DCPS and press and hold power button it jumps to ~90mA and stays there. No short on VCC_MAIN or battery. I also tested TriStar 1v8 and 3v0 lines and it shows 0v. My guess it is either PMIC or NAND. Do you have aby suggestions? Thanks in advance.

06-21-2018, 18:01	#2 (permalink)
Amr.OKa Freak Poster Join Date: Jul 2014 Location: Egypt Age: 31 Posts: 137 Member: 2219780 Status: Offline Sonork: 100.1662738 Thanks Meter: 52	Error 40 Nand not detected

06-21-2018, 21:02	#3 (permalink)
karoliens Junior Member Join Date: Mar 2017 Posts: 14 Member: 2690483 Status: Offline Thanks Meter: 1	I know that it is related with NAND but it could be either NAND itself or PMIC. I will try to test NAND power lines. If they are not present then it should be PMIC.

06-22-2018, 06:41	#4 (permalink)
elecsoluces Major Poster Join Date: Feb 2018 Location: FRANCE Posts: 45 Member: 2816075 Status: Offline Thanks Meter: 8	Hello, You should check the PP3V0_NAND line, if it is shorted one of the caps on this line is defective.

06-26-2018, 17:44	#5 (permalink)
karoliens Junior Member Join Date: Mar 2017 Posts: 14 Member: 2690483 Status: Offline Thanks Meter: 1	Just an update. I have checked PP1V2_NAND_VDDI, PP3V0_NAND, PP1V8 lines and all of them are present therefore I suspect NAND itself. What do you think?