Help, there is no sound in the rear entertainment system of the car, the main control is a MST779-0051 chip from MSTAR

littleshrimp

Help, there is no sound in the rear entertainment system of the car, the main control is a MST779-0051 chip from MSTAR [Copy link]

There was always no sound in the rear-seat entertainment system of my friend's car, and the central control screen did not work well after being set up. Later, I took it apart and looked inside, but could not find the audio output.

After opening it, I found a MST779-0051 chip from MSTAR. The data sheet I found only had register configuration but no pin definition. Now I'm not sure if we didn't understand it or if this thing was not designed to let people in the back row hear the sound. Does anyone understand?

This is a video of the disassembly research process:

chunyang

You have to confirm the configuration first. The rear entertainment system must first have speakers, display screens, etc. You should ask the salesperson when you buy the car. Buick has skimped on the configuration and sold it at a high price in disguise.

littleshrimp

chunyang posted on 2023-3-7 20:40 You have to confirm the configuration first. The rear entertainment system must first be equipped with speakers, display screens, etc. It is better to ask the salesperson when buying the car. Buick has reduced the configuration and bought it in disguise...

This is a car from the Middle East, and the after-sales service is not good.

I think if it makes sense, it should have an audio output, and then output it to the car amplifier through a bus, but I measured two of the lines and there was no analog audio sound.

chunyang

littleshrimp posted on 2023-3-7 21:07 This is a car from the Middle East, and the after-sales service is not good. I think if it is reasonable, it should have audio output, and then output to the car amplifier through the bus, not...

In recent years, cars are all digital, and everything is done on the bus. Rear-seat entertainment is usually an optional facility, which is connected to the bus to exchange audio and video data and control (the rear-seat control actions should be visible on the front-seat main screen). Optional facilities are related to the price of the car. Sometimes the salesperson will say that they are free, but when picking up the car, there may be mistakes due to inventory transfers, and some car owners are too lazy to pursue it. This kind of "trick" is not uncommon. Regardless of whether the after-sales service is good or not, you should first ask for an explanation. Often, you will get it if you ask for it, otherwise you won't. In addition, pay attention to the car purchase contract. Here is a reminder for netizens: For non-standard optional facilities, whether you buy or "give it away", you must write it clearly in the contract, including functions, specifications, arrival time, whether it is original, etc.

chunyang

It is recommended to observe the speakers and screens in the back row (if any), and if necessary, disassemble them to see if there is a circuit board. It is easier to judge based on the circuit board. In other words, you have to disassemble the back row, and it is difficult to determine by looking at the host. Even if it supports rear entertainment, it will be useless if the equipment is not installed or the installed equipment is not compatible.