BMW 556uw bypass wiring

Key in RED / Green and RED / Blue (?) 12V+ Key position ACC above and Violet (purple) 12v+ Key position to IGN, Above and Light Green to 12V+ Key to start (run, crank etc.) All of the above plus Blue/Black. BMW, apart from some Porsches are the only manufacturer to have ACC at 12V+ during the crank cycle.

Based on howie II's Ignition list. The vehicle ACC comes on first then IGN with ACC, then Start(CRANK) with ACC and IGN. Leaving all connections as they are. You will also need to connect the GTS Blue ACC wire to the 87a of IGN2 relay so it will power the Vehicle ACC until GTS IGN2 Activates taking over powering the vehicle ACC including the Start. Thus Matching the key switch. If the IGN2 relay is staying on all the time and the C3/13 White is not turning off. Wire the IGN2 86 to IGN1 in stead of constant +12v. Then when GTS IGN1 comes on it powers the coil to turn on GTS IGN2 to take over from the GTS ACC So vehicle ACC stays on during START(CRANK).

You can get a better solid 12V+ for + brake switch output at the rear of the lighting switch, comes out easily BLACK/ green, or BLACK/ blue.

Sorry, I didn't read anything after this morning and went right to checking the wiring after work. I did confirm everything as far as wiring and I ran into some issues or should I say realization. This car is so old I guess and the key ignition cylinder worn, that you cant even feel a missed position. after testing and turning the key real slow, I noticed there was a position for acc. so that was my fault but my original wiring should have been correct if that was the case. position 1 acc triggers the purple wire 12 volts position 2 IGN 1 triggers the green wire 12 volts with acc on final position 3 (crank) triggers the blue black with acc and ign1 on exactly like Howie said. I tried checking the IGN2 C3/13 white wire on the GTS was enabled through the programing section (1-8) #2 but for some reason the valet switch is no longer working with no visible issues of faulty wiring. The relay switch is not triggering at all to the c3/13 wire and I even tried rewiring it per their discription just incase. If I cant confirm if the c3/13 or change the function option for C3/13 than I cant see going forward on this without finding/fixing the issue with the valet switch. I'm also not getting any kind of reading from the C1/Orange starter wire even with the key in position 2, which would let me start the car with the push button before installing the 556UW (only had one key at the time) Current wiring: GTS= (C1)Red --BMW Ignition Harness =RED / Green 12 Volt Constant. GTS= (C1)Blue ACC --BMW Ignition Harness =Purple (ACC). *556UW pink wire and relay #30 (ign2) GTS= (C1)Brown (Ign1)--BMW Ignition Harness =Green (IGN 1). GTS= (C1)Orange (starter)--BMW Ignition Harness =BLACK/ Blue (Starter). GTS= (C3/14)PURPLE / white (start enable input-)-- BMW Clutch Pedal Harness. GTS= (C3/18)BLACK/ white (foot break input-)-- BMW foot break Pedal Harness (BROWN / yellow). GTS= (C3/17)WHITE/ red (GWR) ---556UW=blue GTS= (C3/13)white(IGN2) relay #85 Relay power #86/87 is tapped into the RED / blue of the ignition harness Everything else works as far as the GTS..doorlocks/rfid. I did not hookup an aux/horn/siren/parking lights or any other possible features till I get the push start feature working.

howie ll wrote: You can get a better solid 12V+ for + brake switch output at the rear of the lighting switch, comes out easily BLACK/ green, or BLACK/ blue.

That's a great idea, if I get this working I can do the relay/parking lights C3/12 at the same time.

lurch228 wrote: You will also need to connect the GTS Blue ACC wire to the 87a of IGN2 relay so it will power the Vehicle ACC until GTS IGN2 Activates taking over powering the vehicle ACC including the Start. Thus Matching the key switch. If the IGN2 relay is staying on all the time and the C3/13 White is not turning off. Wire the IGN2 86 to IGN1 in stead of constant +12v. Then when GTS IGN1 comes on it powers the coil to turn on GTS IGN2 to take over from the GTS ACC So vehicle ACC stays on during START(CRANK).

I will try it as soon as I figure out what is wrong with the Valet switch to confirm C3/13 is active.

howie ll wrote: BMW, apart from some Porsches are the only manufacturer to have ACC at 12V+ during the crank cycle.

Someone shoot me...the next car is a Porsche 928S

malevolent wrote: lurch228 wrote: You will also need to connect the GTS Blue ACC wire to the 87a of IGN2 relay so it will power the Vehicle ACC until GTS IGN2 Activates taking over powering the vehicle ACC including the Start. Thus Matching the key switch. If the IGN2 relay is staying on all the time and the C3/13 White is not turning off. Wire the IGN2 86 to IGN1 in stead of constant +12v. Then when GTS IGN1 comes on it powers the coil to turn on GTS IGN2 to take over from the GTS ACC So vehicle ACC stays on during START(CRANK). I will try it as soon as I figure out what is wrong with the Valet switch to confirm C3/13 is active.

C3/13 has 2 functions active with ACC, and ON or active with ON, and START(CRANK) It should never be off all together when PTS is the ON state. Even if you can't get the C3/13 working just use a direct ground for relay 85 and 86 to IGN1. As long as 1 side of coil is switched it will only turn on when IGN1 is on.

lurch228 wrote: C3/13 has 2 functions active with ACC, and ON or active with ON, and START(CRANK) It should never be off all together when PTS is the ON state. Even if you can't get the C3/13 working just use a direct ground for relay 85 and 86 to IGN1. As long as 1 side of coil is switched it will only turn on when IGN1 is on.

I was thinking the same thing if I cant figure out the valet switch...maybe I just forgot how to count to 5 and hold...good thing I still have all my fingers.