How to repair a bricked RNS 310
Posted: 24 Sep 2022, 09:08
Hi guys,
i've bought a cheap RNS 310, usually used in Volkswagen cars (VW, Skoda, Seat, ...). This version was build from Bosch, as the familar FX, NX, MCA devices. It also uses nearly the same components.
The problem with this unit is that it does not start, or better, it nearly don't start. When applied to 12V it boots up internally (CD-drive init) and draws about 650 mA. When pushing the ON tipper the button light turns on and display shortly initializes (no image, only background light), but no picture. After some seconds it turns off again. This can be repeat several times.
First i've checked the RAM chips, as they are the same as in the Ford satnavs and so i suspect they got the same problem. But heating the RAMs did not change anything on the behaviour.
Next, i reflashed the device with a known working Firmware image of another RNS310, but also not change. Reflash is the same with JTAG as for the Ford devices. The RNS 310 uses the same headers/pinlayout on the lower side of the mainboard. The Flash has a size of 64MB like the NX/MCA devices and one can use the Flash-Project for Segger J-Link for it without a change.
Other than the Ford devices, it seems that there is no extra watchdog on the radio-processor, so for reading/writing the Flash, no extra jump-wire connection is needed.
Now, does anybody here got some experience with those kind of devices and their typical hardware failures?
i've bought a cheap RNS 310, usually used in Volkswagen cars (VW, Skoda, Seat, ...). This version was build from Bosch, as the familar FX, NX, MCA devices. It also uses nearly the same components.
The problem with this unit is that it does not start, or better, it nearly don't start. When applied to 12V it boots up internally (CD-drive init) and draws about 650 mA. When pushing the ON tipper the button light turns on and display shortly initializes (no image, only background light), but no picture. After some seconds it turns off again. This can be repeat several times.
First i've checked the RAM chips, as they are the same as in the Ford satnavs and so i suspect they got the same problem. But heating the RAMs did not change anything on the behaviour.
Next, i reflashed the device with a known working Firmware image of another RNS310, but also not change. Reflash is the same with JTAG as for the Ford devices. The RNS 310 uses the same headers/pinlayout on the lower side of the mainboard. The Flash has a size of 64MB like the NX/MCA devices and one can use the Flash-Project for Segger J-Link for it without a change.
Other than the Ford devices, it seems that there is no extra watchdog on the radio-processor, so for reading/writing the Flash, no extra jump-wire connection is needed.
Now, does anybody here got some experience with those kind of devices and their typical hardware failures?