Trouble starting my 2003 360

Thanks! I guess the next step is to see if power is getting to the red/green wires with the ignition on.

If ok, then tracing the red wire aft via plug 12D/19D

 

red and green does have power i check already

 

Here's the location of 12D/19D

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Seems to be under the dash in line with the centre console.

Then the red wire goes to a splice (location unknown). If all the brake lights are not working (including the high one), the fault must lie between the pedal switch and the splice (including the splice).

Can you think of any work that has been done on the car recently which may have disturbed the wiring?

 

Revised photo notes:

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Revised Modena Instrument wiring diagram:

https://www.dropbox.com/t/PQMXljlC7AE912Xu

Revised Spider Instrument wiring diagram:

https://www.dropbox.com/t/PnnjIDGfscOxdneV

 

Plug the switch back in..key on..remove the connector from the back of the tail light assembly..apply the brakes check for power and ground at the tail light assembly itself. Let's do the easy stuff first..before we go ripping apart the interior..

Another thing to check..do the tail lights work when you turn on the headlights etc? signals flash etc..

 

I'd say it was a power issue, not a ground issue. The brake switch sends 12 volts to the F1 TCU, hence no start. The L, R stop lights and high stop light probably all have different earths, as will the F1 TCU, Suspension ECU and RH Motronic ECU.

Since you probably have the fuse box covers off behind the RH hand seat, you could check power on the red wire on plug 16G/11P or even power on the red wire at the F1 TCU itself (pin 17 on the upper plug).

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From a different angle:

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F1 TCU 9P connector (upper)

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The single splice S35D in the wiring diagrams may not be a single splice, but a series of splices along the wiring harness.

Here the path of the red wire as it emerges from the rear end of the centre console:

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Plug 6G/11G may be easier to access than that forward plug under the dash.

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If no power here with the brake pedal pushed, work forwards. If you can confirm the LH brake light isn't working, the wiring break must be between the rear of the centre console and the brake pedal switch.

Note: I'm not sure if you will set any additional messages with 6G/11G disconnected with the ignition on.

 

ill check into it this weekend recovering from surgery on right arm had a bunch of DR. appointment and physical therapy. i know there is 12 volts to both the red w/ green striped wires and i can trace the wires from the switch to the first connector (12D)

 

only the two outside lights/blinkers work the two inside and upper brake lights do not. i do have 12v on red(20) at 6G

 

Sorry, not sure what country you're in. Are your lights like this:

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Or do you have outer brake lights, too?

I don't understand why you're not getting the LH brake light to work. The LH brake light is upstream of 6G (power-wise).




Shorts can drag down the system, but you would think that that would blow the fuse.

Can you try testing the left brake lamp with 6G disconnected?

Also, can you find 16G and test for voltage on the red wire there with the brake pedal pushed (with 6G connected)?

 

Good news bad news. All the brake lights are working but I still cannot put the car in gear.

 

Have you confirmed the pump runs when you open the drivers door? And have you checked the level in the F1 fluid resiviour...

 

Pump runs fluid is good I can activate the gear box using my Foxwell scanner all gears including reverse are accessible

 

Can you figure out how you went from this...

to this...

Perhaps you got a better connection by resetting plugs.... or it was finger trouble (or in your case arm trouble). Get well soon.

Assuming the voltage from the brake pedal switch is getting to the F1 TCU, then I'd better hand this over to the F1 experts. You should never assume, of course. You could check for brake pedal voltage at the F1 TCU plug itself (assuming the plug is not too hard to get to).

I assume this is the starting sequence...
1) Brake pedal allows gear change to neutral?
2) Neutral allows the F1 TCU to enable the starter relay?

Note that the Immobiliser (when disarmed) sends an earth to the F1 TCU and the F1 TCU passes this earth along to the starter relay solenoid (if it is happy that the car won't run into a brick wall when you engage the starter).

 

Does your scanner have a data stream reading? Are you able to see the system pressure? should be in and around 43-45 bar.

 

It does have live data I’ll check tomorrow I’m done for the night.

 

When I was chec

 

When I was checking for voltage at the right brake light I unplugged the light and the left brake light went on. I switched the bulbs to make sure the led assembly was not the issue so the right light worked on the left side switched them back and they both worked.

 

I’m still focused on the switch. Live data from the Foxwell shows the brake switch is alway off even though the brake lights function

 

Interesting. It's probably time to test the voltage at the F1 TCU itself. If it is present at the plug, then I guess it's a TCU issue.

You're looking for volts on pin 17 of TCU plug 9P (the smaller of the two TCU plugs). If no volts with the pedal pushed, work backwards to plug 16G.

(EDIT: Sorry, lack of familiarity with the 360, I thought the TCU would be hard to access.... Actually looks quite easy, but be careful when removing/installing the plugs)

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Did the battery cut off over night. This morning started the car and paddle shifted into first. IT WORKED! Tried reverse IT WORKED. Opened the garage and drove it around no issues. Troubling part is i still do not know the cause. I did nothing but unplug and plug the above listed connections and check for voltage.

 

Weird to say the least. Perhaps it was a combination of factors causing the TCU to get confused and a battery reset was all it needed.

Speaking of confusion, after reviewing the thread, I just realised that you said the starter was working, so my guess at logic was wrong:

Is the brake pedal required for both starting and gear changing from neutral?

Anyway, let’s hope the problem stays away. Thanks again for testing the brake pedal switch. That’s been bugging me for ages.

 

don not need the brake pedal to start it but you do need it to put the car in gear. I do believe after the brake lights started working it needed a rest (battery cut off)

 

So if the car is already in neutral or first gear, you don't need the brake pedal to start the car? Or do you need the brake pedal only if the car is in first gear (as the TCU has to change to neutral and depress the clutch)?

 

Car will only start in neutral and no brake necessary to start it.