Huawei ETS6x8 Service Manual Troubleshooting guide

ETS668

11. Troubleshooting Guide

Huawei Technologies Co., Ltd.

ETS668

11. Troubleshooting Guide

11.1. Troubleshooting of LOGIC Block

In case of Booting Reset(repeat)

11.1.1. In Case of Power ON	>> PAM(U202 #5(Short checking)>> change

Press the button PWR.

Yes

````````````````

Can the power be conducted to #1 of U505, #4 of U506?

You should check and repair No the line from BATT. power via

D500 and Q500 to Q501.

Yes

Can 2.7V, 3V be conducted to VDD U400?

You should check and repair No the related and surrounded

circuit for U505, U506.

Yes

Can it be conducted more than		No			You should check and repair
3.4V to #1 for U505 and #4 for U506?					the U505, U506 surrounded circuit.

Yes

End

Huawei Technologies Co., Ltd.

ETS668

11.1.2. Initial operating failure

Press the button PWR.

Yes

Can it be generated the RAM_CS1_N

You should check the

signal for U400 #P14 and the ROM_CS1_N

No

output for CLK from U301 #4

signal for U400 #R15?

with 19.2MHz

Yes

Can it be inputted for TCXO to

You should check

and

No

repair the output TCXO

U150 #36?

from F300 #3 and C310.

Yes

Can it be outputted for CHIPX8 to

You should check

and

No

U400 #A14?

re-download S/W

Yes

You should check

and

Can it be on for LED D517?

No

repair the related and LED.

Yes

Can it be showed the initial screen

You should check

and

No

on LCD panel normally?

repair the related and LCD.

Yes

End

Huawei Technologies Co., Ltd.