Actually, I meant your gear selector panel light on the centre console. Do the buttons or other parts of the panel illuminate when the ignition is on or only when the sidelights or headlights are on? Also, are they dimmable? Maybe the batt/12volts fault was only triggered when the lights were on, due to a short to the panel backlighting power wire to pin 5 serial data wire See if the voltage on pin 5 changes with the sidelights or headlights on. See if it changes value with the instrument light dimmer at different settings. You may have to backprobe the plugs to get a voltage reading.
The f1 displays the gears or neutral all the time As I said it dims if headlights are on or driving lights It can also be dimmed by the dash dimmer
If that’s what your talking about all the lights there follow the dash lights for on, off, and brightness
So these areas illuminate the same as the instrument panel backlighting? Image Unavailable, Please Login I wonder if the input on pin 9 of the display (from the instrument lighting system) goes straight through the panel to pin 4, then to the gear selector (or whatever it's called). Image Unavailable, Please Login I was thinking that if there was a short between the lighting wire on pin 4 and the data wire (pin 5) the 10 volts on pin 5 might change depending on the instrument light dimmer setting.
That selector panel also has a pcb board and some chips so it could do many things. I do not think the system will function without it plugged in
Would the light also be dimmable because it does dim with the dimmer switch which I think you asked me above and it does. It seems like it’s a little different scale but when you go brighter it does and when you go dimmer it does just at a lower voltage I think. From what I remember I think it’s a bit dimmer usually. Someone else with a F1 could confirm but from what I remember it is different.
I have tried to change gears through the paddles with just ignition on with the mode selector panel disconnected. But nothing happens.
I will check this out. Maybe pin 9 is not giving the proper resistance it should. Do you have any wiring diagram for the mode selector panel??
So eric asked me to trace the pin 25 line inside the TCU. Traced it as much as I could. Didn't see anything out of the ordinary but then again I'm not an electronics guy and don't know much about circuit boards. Does anyone have any TCU repair contacts? https://drive.google.com/drive/folders/1Px11yuiP5vX8OnKxH4YfbKKFGAnFUQIf
Also yes the lights on the mode selectors illuminate with the instrument lighting. Also pin 9 says it's the rheostat input. That is from the dimmer.
I got a new problem now. 2 days back I was using the SD1 to shift gears. Did a cycle of all the gears start from 1st. Went upto 5th gear with the pump cutting on and off as usual. Then it wouldn't engage 6th. Thought maybe pressure dropped but from the live data it was at 55bar. But it still wouldn't shift. Left it alone for about an hour and came back to attempt the shift and then it wouldn't go into any gear at all. It attempts to go into gear. You can hear the actuator moving and attempting to go into gear but when it displays the min current and max threshold values the current threshold value was above max. I don't know if the solenoids got cooked or the TCU isn't providing enough current to the solenoids anymore for it to be able to slot it into gear. Will attempt to operate the solenoids myself by using the chart from the manual today. I feel like setting the car on fire and sit there and have a beer while watching it turn into a crisp.
What is this? I can't get access to your Google Drive. Yes, I know pin 9 is from the dimmer. I just want to make sure the voltage from that (or from the dimmer voltage on pin 4 going to the reverse gear selector panel) is not getting to the serial data wire on pin 5. At max brightness, it might be producing 12 volts on pin 5 and the TCU is interpreting this as a "short to Vbat". The "short to Vbat" is the only clue we have, but it may be just an irrelevant glitch. You could have any kind of kind of problem causing the display to show dashes, including your current gear selection problem. If your gearbox isn't going into a valid gear, the system may be producing dashes on the display. Maybe you could just make sure that the wire on pin 5 is not shorting to the wires on pin 9, pin 4 or pin 2, then we can focus on the TCU and the rest of the system. You only have 10 volts at the moment (which seems to be normal), but the instrument brightness may change that.
Sorry the access permission was on restricted. I have changed it. Its just a few videos of tracing the pin 25 in the TCU. So when I set my multimeter to continuity or beeping, as some people call it, to check the connection between 2 points, I do get a beep between pins 5 and 2 with ignition on and TCU connected or disconnected and even if the dash board connector is connected or disconnected. I also get a beep from pin 5 to 6,7,8 which are the lines for the warning lamps only if the warning lamps are not illuminated. But with the ignition off I do not get any continuity between any of the pins to pin 5.
You shouldn't be doing continuity checks with power on. Continuity checks involve the ohmmeter sending a small voltage through the circuit to measure the resistance/current. If you start introducing 12 volts from the car, then resistance can't be measured properly. Is this with the TCU and display disconnected. i.e. checking from wire to wire, not through the display or TCU? I don't know what kind of circuit there is between these pins, so I don't know if it is important or not. Obviously, the ignition volts on pin 2 should not be going directly to pin 5. There will be some kind of integrated circuit for handling serial data. I looked at the videos, but I didn't know what I was looking at. Did pin 5 go to an integrated circuit of some kind? What is the black probe of the ohmmeter attached to? Pin 25?
This is with the TCU and dashboard connector disconnected. The display unit is connected. Without the display unit no wires have continuity. Did you want me to just check resistances between all pins with the display and TCU disconnected? Because I have done that as well and pins 6,7,8 have a very small resistance with ignition off because they all become ground when ignition is off. Yes the black probe is connected to pin 25. The path ends at that black component 2901. I was basically just trying to check from where the pin 25 gets its signal. Eric had asked me to do this so I thought I'll share it here as well.
Thanks. It wasn't sure if you had done this already. I asked this in post #8, but I don't think I got a clear answer. Regarding your first video: Image Unavailable, Please Login Assuming that component is attached to pin 25, I don't know why you have continuity on this side of the component, but not on the other side (closest to pin 25). Even if that was a diode, that doesn't make sense. Is there a direct physical link to the top end of that component to pin 25 (on the other side of the circuit board)? If there is a direct wire between pin 25 and the top of that component and no electrical continuity, I would be resoldering pin 25 and that component. I would be very careful with heat, especially with such small components. Resistance values might be more meaningful (rather than beeps) on this connection. Unfortunately, once you get deeper into a circuit, resistance checks become meaningless. You don't know if there are other resistances/components in parallel.
Filtering capacitor there. Connected to pin 25 on 1 side and to ground on the other side. Very common and nothing wrong.
This is how the PCB is designed. Loot at the picture, all these capacitors have the side close to the pins connected to ground. Their other side is connected to the pins through tracks on the other side of the PCB.
