How SIM Card Work In Mobile Phones

Sample Nokia because its all systems on the basis of his work similar

At pin Simcard must consist of 6 Pin .. consisting of:

Nc (Not Connetcetd)

all phones must be composed of six pins is just ….

Consider the following schematic:

1If we look at it … workflow from the sim card is ….
From the sim connector ===> ====> Simcard Emif Power Ic
This applies to all phones ….

In detail we take the example image below:

2This point should we really understand …. because the work will be very decisive steps which we will do ….

PIN2 is important that we have noticed is all the PIN2 must be in a state connected to each other according to the path … except for NC path alias not connected or not connect to mana2

STEP 2 simcard in determining damages is ….

1. Simcard replace first … lest we not read sim card mobile phone sim card because it is damaged … oon’s really tuh hehehheheh
2. If the sim is ok … measuring inhibition of 5 pins in it … VSIM particular point, the data sim, sim sim clock and reset ….

PIN2 is to determine where on the connector … the steps we need to do is to determine which point PIN2 Ground on the sim card connector ….

You have to understand … that the ground would be in one corner of the sixth PIN2 .. as shown below:

3If you notice … then the ground of the sim card connectors are located on the bottom right corner …

to determine the next titik2 ….

that is certain!!
ground position to deal with VSIM
On the ground must have NC
His next composition of the next sequence certainly like the picture above ….

Well,.,, After we know titik2 of PIN2 in accordance with its name … then the next step is … by measuring the resistance in the pin data, clock, reset and VSIM ….

if there are no obstacles in the climb, … hence can be sure that your cell phone damage is a line break between emif simcard with connectors or damage to the emif simcard ….

steps you should do is … by lifting emif sim card … then measure the correlation between the broken lines in accordance track down emif sim …

if the line is not severed was good aka .. hence can be sure that … emif simcard must BROKEN! solution is to replace or men jumper emif emif simcard simcard in accordance with the track … for example at the above phone .. jumper the trick is as follows:

4The next ……
if it turns out after doing resistance measurements in the … all the normal barriers .. (If necessary, compare with the value at normal cell phone)
then … steps should be done is by measuring the voltage on the connector …. VSIM measuring at the measuring point in accordance with the determination of this VSIM pin …

VSIM measurements should be made on the phone the first time in the light … Why? because when the phone is the first time live … then he will check the existence of sim and will appear voltage of 1.8 v. .. if the mobile phone sim card does not detect the presence of the tension that had been at 1.8v will fall directly on the point of ZERO … but if the phone can detect the card then the voltage will be increased to 3 volts …

so do not be surprised .. if the phone had been living so many seconds … you will not be able to measure the presence of voltage at 1.8v the sim card … this is what often happens and becomes kekeliaruan .. and always raises the question … “Kok kok VSIM voltage measurement his breast I not ever stress ya ????”


more … if after doing measurements proved that the voltage stress is apparently no voltage NOL aka … then it should do that best is to replace the Power Ic .. because the stress is coming from the UEM … but .. replace the IC power because it has a big risk …. and also requires a high cost due to power ic pretty good price … then … the stress is enough to outsmart us by fetching from another voltage …

Whether the voltage from which we’d better get me??

you do not take away from the stress of other 1.8v .. example taken from Fio … because the possibility of success will be very small ….


because when simcar unreadable … there must be a voltage of 3 volts instead 1.8v ….
8.1 The stress voltage is the basis for detecting the presence of sim …

The most appropriate is … by making jumpers from 3-volt voltage for others ….

nah on the phone because we very rarely voltage 3 volts .. then we usually menjumper of voltage at 2.8v .. example of the Vaux voltage of 2.8v …..
this forum actually do have a jumper from Vbat …. and successful …
it is okay to do .. and will be successful .. but because there is excess voltage that should only 3 volts (VSIM) to Vbat (3.7V) .. hence the risk it faces is the possibility of rapid destruction of our CIP sim card ….

The next step ….

if we measure it on the path constraints VSIM not normal .. aka height .. then we have to do is to disconnect the capacitor on the path that led to ground .. because damage to the capacitor on the line can be caused sim unreadable …

Here are disposed capasitor2:

Note the capacitor which given a yellow color ….

5capasitor2 unplug serve targeted if the obstacle in the path simcard problem ….

Next ……..

If we measure it all turned out normal barriers … The next step is to lift emif sim … then measure the resistance in between emif Power Ic simcard that led to the one in emif … the goal is to find out .. whether between emif simcard and power ic …. there is a line break

if there is no increased resistance value .. hence can be sure that there is line break between emif and power ic .. then the solution is to jumper between emif simcard into power ic in accordance with the broken lines …

If after performing the measurement .. apparently all the normal barriers .. then jumper simcard emif first … if after to jumper emif simcar normal direct phone .. hence can be sure the damage to emif ….

but if it turns out after to jumper emif … no sim card also read … hence can be sure damage to the power ic ….

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