[darkmcs]

Hi,

I bought a SmartTV module a while ago (enables to play DVD while driving)

I saw the warning on the website (mods4cars) regarding an issue with a few BMW models. (see below):


We recently discovered a problem when any of our modules is installed in a newer model BMW with switched power supply. Especially 6 Series and 3 Series with Comfort Access (keyless entry and keyless engine start/stop) seem to be affected. These cars turn off the power supply to most of the control modules when the car has been idle for more than 15 minutes. This measure is designed to prevent a drained battery when the car is sitting for prolonged periods of time.

Unfortunately this conflicts with the standby power saving mechanism of our modules! Our modules have a sophisticated self-power-down standby mode in which the processor in the module is turned off, but immediately wakes up when any data traffic is detected on the data bus. The module itself consumes only very minimal power in this mode. It is mandatory that the module is permanently powered. Otherwise, on cars with keyless access where the circuit with radio and top control unit is NOT powered up upon touching the door handle or trunk button, the module is left unpowered and unable to receive or transmit any data.
Our module, much like a network router, receives and transmits data packets on the car's data bus. If the power is interrupted, no communication across the module is possible, data is blocked! This leads to other control modules permanently trying to communicate and thereby draining the battery.

If you get any error messages about power drain, a battery warning or a workshop symbol, or if the trunk button does not react after the car has been sitting for a while, this is the reason why.

In car electric terminology a wire with permanent power is called "Terminal 30", a wire with ground is "Terminal 31" and a wire powered by the ignition circuit is "Terminal 15". BMW introduced the standby power-down circuit "Terminal 30G" which is where the radio and top control unit are connected to.
Solution: Disconnect the power wire from the thick red power wire to the top control module (smartTOP) or the radio (smartTV) and connect it to an unswitched (Terminal 30) wire, directly to a fuse powering a Terminal 30 circuit, or run a wire (with inline fuse!) directly to the battery "+" terminal.
We recommend getting a ~6ft long power wire with 1 or 2 Amp. inline fuse, available in car accessory shops for example to hook up radar detectors or CB radios.

Now my question is: Which fuse could I tap in to get that "Terminal 30 circuit" (aka unswitched wire, with continuous power to it...)

Thanks a lot!!