Since I was already giving up on the issue, I decided to test the unit without any interface on the processor. The unit booted normally, reaching 100°C without rebooting or shutting down. So I decided to test again with a replacement thermal pad that usually comes with M2 drive heatsinks. And surprise, I once again got stable temperatures of 50°C without rebooting, and maximum temperatures of 72°C with a CPU stress test. Very strange, because I had already tried using these thermal pads without good results.
Dudu7 head unit reboots by itself
- Edited
Arielnac Could you provide photos with the backplate off? Could the backplate be trapping heat against the circuit board and maybe affecting other chips possibly causing the reboots? Maybe the SOC overheating isn't the issue.
IamDefiler Hi. No Friend. When the unit fails, the CPU temperature readings are high. When it's working properly, the temperature readings are much lower. The problem is the CPU.
Arielnac Only reason I asked was because of what you stated above. "The unit booted normally, reaching 100°C without rebooting or shutting down."
Mongcharlie I also have SIM card inserted and data always on. My unit is continuing to reboot randomly (approx once a day when in use for several hours). It is frustrating when using it for navigation on unfamiliar busy city roads. I am now thinking the only solution may be warranty claim with seller.
7 days later
IamDefiler Yes. But that was just a test condition, without subjecting the processor to any type of load, and to see if there really is any difference between placing some type of interface between the CPU chip and the aluminum heatsink. And there is. The problem is that under load, at some point, the CPU temperature shoots up and it either reboots or crashes. I've verified this because while AIDA 64 shows me temperature values below 50 degrees, the unit runs stable. When it starts showing values above 70 degrees, just listening to music with a low CPU load that doesn't justify that operating temperature, it's just a matter of time before a reboot or crash occurs.
The factory fan may have too low airflow. You'd need to remove the factory fan and replace it with a 40 x 40 x 25 mm fan to increase the airflow over the aluminum heatsink.
Arielnac I understand. Thank you.
IamDefiler What may be happening is that when the outer casing heats up a bit due to the audio amplifier chip, the air blown by the fan over the internal CPU heatsink is too hot and doesn't generate enough temperature gradient to cool the CPU. Removing the factory fan and installing a 40 x 40 x 20 cm external fan in the same air intake location would likely generate enough temperature gradient.
Arielnac what is the voltage of the stock fan? I have been thinking about updating mine, but would like to order a fan before tearing it apart.
4 days later
tsbrewers Hi. Is 12 Volts. I've already made the modification. I removed the factory fan and installed a 40 x 40 x 20 mm external one. Now the aluminum casing above the CPU cools much better. Previously, the entire casing would heat up due to the heat generated by the amplifier chip, and the factory fan is very small.
Thank you, I appreciate the reply and the great pictures.
And probably part of the problem is that the TDA 7808 amplifier chip generates much more heat than the TDA 7803. That's another argument I've had with the seller. They say the 7808 is the same as the 7803, but I'm sure the TDA 7808 is a defective version of the TDA 7803 that generates a lot of heat and is only recommended for use with 4 ohms speakers. The TDA 7803, on the other hand, can handle 2 ohms speakers.
Wenn uch mir überlege wie groß die 2-Din Radios waren, und wie viel Platz nun hinter den Radios ist, könnte man sich vielleicht auch eine andere Kühllösung einfallen lassen.
Gestern hatten wir gerade einmal 20 Grad Celsius, das Armaturenbrett war natürlich warm durch die Sonne, aber der Lüfter hörte nicht auf zu laufen.
Temperatur vom Prozessor lag immer bei ca. 65 Grad Celsius und mehr.
Das habe ich selbst im Sommer mit dem ein Jahr alten DUDU7 NICHT gehabt. Vor allem habe ich bei dem alten DUDU7 den Lüfter niemals gehört, weil der so leise war.
Die neuen Lüfter sind dagegen laut wie Turbinen.
JhonnyD The fan I used is actually quieter than the original factory one. It's much more efficient because it has much greater height and pitch of the blades. The original one is only 7 mm thick. The impeller of the one I installed is 17 mm thick. It actually cools the aluminum and it seems to be sufficient to keep the CPU from exceeding operating temperature.. The factory one doesn't generate any cooling effect on the aluminum.