Keypad Backlight Troubleshooting; Audio; Audio Troubleshooting - Nokia 2366i Baseband Description And Troubleshooting

2366i (RM-155)
Baseband Description and Troubleshooting

Keypad Backlight Troubleshooting

Refer to Figure
checks.
1. Perform a visual inspection of the LCD connector and the all the components,
including the LEDs.
2. Check Vbat to ensure that the LED Driver IC has power.
3. Check the Klight signal to ensure that the driver is enabled by the UEMCR IC. If
not, check the UEMCR IC.
4. If the lights are too dim or too bright, check the current setting resistors. Resistor
Rset controls the current going through the LEDs.
5. Check the output of the LED Driver to ensure that the LEDs are receiving power. If
the output voltage is present, replace the LED.

Audio

The Baseband PWB supports three microphone inputs and two earpiece outputs. The
microphone inputs are:
• MIC1 - used for the mobile terminal's internal microphone
• MIC2 - used for headsets connected to the Pop-port connector
• MIC3 - used for the Universal Headset connected to the Universal Headset Jack
(UHJ).
Each microphone input can have either a differential or single-ended AC connection to
the UEMCR circuit. The internal microphone (MIC1) and external microphone (MIC2) for
are both differential for Pop-port accessory detection. However, the Universal Headset
interface is single ended. The microphone signals from different sources are connected to
separate inputs at the UEMCR IC. Inputs for the microphone signals are differential
types. Also, MICB1 is used for MIC1, and MICB2 is used for MIC2 and MIC3 (Universal
Headset).

Audio Troubleshooting

Use the following to troubleshoot the audio:
1. Check for bad contacts or a damaged earpiece.
2. Check for bad connections at the mic, and ensure that the Audio ASIP is OK.
3. Check for broken or bad solder joints on passive components.
4. Verify the audio signal paths, using "BaseBand audio control" feature of Phoenix
See "Audio Phoenix
Page 18
15. When troubleshooting the keypad backlight, make these common
Interface" on page 19.
Company Confidential
Nokia Customer Care
Issue 2 - February 2007