{"id":1738,"date":"2020-04-06T18:21:04","date_gmt":"2020-04-06T17:21:04","guid":{"rendered":"http:\/\/www.beady.com\/blog\/?p=1738"},"modified":"2026-05-21T11:56:29","modified_gmt":"2026-05-21T10:56:29","slug":"bmw-m57-cruise-control","status":"publish","type":"post","link":"https:\/\/www.beady.com\/blog\/bmw-m57-cruise-control\/","title":{"rendered":"BMW M57 cruise control"},"content":{"rendered":"\n

When swapping the M57 into the Dogger I wanted cruise control,. the button was in and I wanted it to work.<\/p>\n\n\n\n

\"range-rover-cruise-control-switch\"
It was fitted to all P38’s I think<\/figcaption><\/figure>\n\n\n\n

The switches from the BMW in the steering wheel use a K-bus data stream into the engine ECU , the ECU does all the necessary stuff and works well.<\/p>\n\n\n\n

But how to get the correct data into the ECU when you don’t have a BMW MFL steering wheel ? well at first I was going to make a little circuit to do this, so I acquired a switch pack from aE46 to sniff the data, but realised it would be easier to repurpose the unit.<\/p>\n\n\n\n

\"BMW
you dont need the M series wheel any with the cruise buttons will do.<\/figcaption><\/figure>\n\n\n\n

so I did, I soldered on these wires to a plug and then linked them to the buttons on the P38 steering wheel and sent the wire with k-bus data to the DDE4 ecu. The cruise and phone buttons are on separate PCB’s and although it’s a funy shape it is a small board.<\/p>\n\n\n\n

\"BMW<\/figure>\n\n\n\n

all the errors in the ECU dissapeared and using OBD reader I could see the button operating but speed input error was still there.<\/p>\n\n\n\n

Now most old BMW ECU’s take the speed signal from one of the rear wheel ABS sensors so I did just that, the signal from the speed sensor on the P38 was the same format, but it didnt work \ud83d\ude41<\/p>\n\n\n\n

I still got the speed signal error!!, turns out the DDE4 ECU wants the speed on the CAN bus… I don’t have a E46 to get the data from, I roughly know the data format but cannot get it to accept it…..continued soon<\/p>\n\n\n\n

unless anyone knows better …<\/p>\n\n\n\n

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What to read next<\/h2>\n