Als Technical Description And Troubleshooting; Dipro (Proximity Sensor And Als) Troubleshooting - Nokia 500 Service Manual

RM-750
BB Troubleshooting and Manual Tuning Guide
The accelerometer and proximity sensors share the same supply voltage and I2C bus with the magnetometer.
You can use both Accelerometer Test and DiPro Test to rule out the possibility that power supplies are broken
(VAUX & VIO) or that the I2C bus is not working on the engine side.
If the detailed results indicate too high data for any of the sensor axes, you first need to verify that there are
no external magnets or magnetized metal parts near the phone that could deflect the sensor. You can test
how the self test fails if a strong enough magnet is brought close to the sensor on the PWB.
In the following figure, the self test has failed because the data on X-axis is too high (Data 80h=1000 0000
in binary format). The 3rd byte in Detailed Result is a key to more accurate data, as seen in the figure. The
Detailed Result information is important when communicating with the R&D regarding magnetometer
failures.
Figure 8 Magnetometer self test

ALS technical description and troubleshooting

DiPro (proximity sensor and ALS) troubleshooting

DiPro Self Test verifies that the sensor can communicate with the host engine. The test does not verify that
the IR LED used with the proximity sensor is functional.
The component's logic circuitry is tested by reading the manufacturer ID from the sensor register. Interrupt
signal 'INT' is also tested by forcing it to change its state and checking it by the engine.
If the self test result is 'No response', the engine cannot communicate with the sensor. The magnetometer
and accelerometer share the same supply voltage and I2C bus with the DiPro. You can use both Magnetometer
Test and Accelerometer Test to rule out the possibility of a power supply failure (VAUX 2.8V) or an I2C bus
failure on the engine side.
If the self test result is 'Minor', a pop-up window will open and the error can be identified from Detailed
Result (see the following figure).
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