User Guide

RAE-6/RA-4
Nokia Customer Care 6 - Baseband Description and Troubleshooting
48 COMPANY CONFIDENTIAL Issue 1 12/04
Copyright © 2004 Nokia. All Rights Reserved.
QWERTY troubleshooting
End
Check connector
X4401. OK?
Yes
Yes
Fix connector.No
Try
another full
keyboard module.
Keyboard
working?
Yes
Yes
Yes
No
No
Is
keyboard
working?
Measure
voltage levels from I2C_sda
(J4416), I2C_clk (J4415) and
KB_irq (J4417) lines when keys
are pressed. Voh ~ 2.8V
and Vol ~ 0V.
Voltages OK?
Change D4400.
Remeasure lines
I2C_sda, I2C_clk and
KB_irq. OK?
No
No
No
Check
R4800.
Resistance
~ 2k2 ohms?
Is
full keyboard
working?
Yes
Put original full
keyboard module back.
Yes
Change
R4800. Remeasure
lines I2C_sda, I2C_clk
and KB_irq. OK?
No
Yes
Fault is in non-
reworkable
component. Refer to
current BER handling
guidance. (OMAP
D4800 problem).
Yes
No
Try another
full
keyboard
module.
Full keyboard is
not working