ESP - BAS - ABS Locked in Park

[onefortheroad]

Ok, thanks for that. I need to do some research on that. I read the post where you said you had a bad earth on the canbus. I need to check what the "canbus" is and where it is. Cheers.

Every electronic unit is part of the canbus , bit like a computer network , they all communicate with each other , if 1 fails the rest panic and cause these issues . Its not a physical part.

 

[mattkh]

Every electronic unit is part of the canbus , bit like a computer network , they all communicate with each other , if 1 fails the rest panic and cause these issues . Its not a physical part.

Thanks.
In that case, what would you say is the overall controller..?

 

[Lozzar]

Appreciate all that. It sounds like my priority is to get the gear out of park and take it to experts. Stuck in the drive at the side of the house with no movement control will mean a really tricky extraction onto a trailer. My love for this car is being seriously tested. Cheers everyone who has messaged.

 

[Lozzar]

My initial study suggests that CAN bus is essentially 2 Wires connecting between every module in the car. So I guess once you've identified the specific 2 wires you can carry out a variety of connectivity checks. One message I read suggested the two wires can be identified because "they're twisted" and identified as coming from the OBD connector at pins 6 & 14. Is their any merit in this?

 

[onefortheroad]

Thanks.
In that case, what would you say is the overall controller..?

Probably the abs pump and ecu . In this instance .


Have tried the brake switch by hand instead of using the pedal. If the rear lights are staying on , the fault is maybe beginning at the switch or ending at the switch. ??

 

[Lozzar]

I have operated the switch by hand yes. I made the mistake of leaving the switch hanging loose and turning on the ignition but of course when the switch spring isn't under pressure it is simulating the pedal being pressed which will illuminate the brake lights. So realising my mistake I squeezed the switch and then turned the key. The result is the Brake lights still came on. The brake lights also come on with the switch in situ behind the brake pedal. But I'll take on board what you say and focus my CAN Bus connectivity testing to the Switch locality and Bus connection. Regards.

 

[Lozzar]

This looks like a good explanation of a generic CAN Bus system??

 

[Lozzar]

Anybody know where this item might be located in the CL500 W215 car?

 

[joderest]

the battery could well be your culprit, they do not like low voltage these cars.
My old ML270 would throw up lights for what seemed no reason, changed the battery ( it was reading 11.9 after resting overnight) and all was fine.
I have been told that anything near 12 volts is a dead battery, 12.7 at the least and 14.4 when running.

 

[mattkh]

I have operated the switch by hand yes. I made the mistake of leaving the switch hanging loose Regards.

How many wires did you see in the connector to this switch..?

 

[Lozzar]

The Brake switch has two rows of three connectors. The top row (as you look from the driver seat) is the Cruise Control and the bottom row is the Brake. I checked the connectivity (resistance) of the new replacement switch and it seems good. On the cruise control there are only two wires (3 terminals). The connectors are designed so you can't swap them. The logic of the switch made sense. When the Pedal is at rest (switch spring under load) the Cruise terminal is open and active then as soon as you touch the pedal (switch spring no load) the Cruise terminals are closed, disconnected and the Brake terminals become open and active. In normal conditions this would illuminate the brake lights, but in my case the brake lights are on anyway, illuminating as soon as the ignition is on. I did do a trace of the Red wire in the Brake connector and found the wire has continuity up to the loom harness that connects into the ESP BAS Module in the fuse box (there's a picture of this module at the beginning of the thread above-page1). Carrying out the voltage check on this connection I had to set the multi-meter setting to 200m on the voltage scale (the scale goes from 600-200-20-2-200m) to detect the voltage on this connection. I reasoned that a switch only needs a small voltage to trigger something. The Module has two wire harnesses with slide motion clamps to hold the looms in place over the pins. The low voltage wire connected directly to the brake switch (presumably an output wire) is in the connector nearest the car bulkhead. The second connector in the Module (away from the bulkhead) had a wire (presumably the input) showing 12.9volt. Each connector had many wires, I just focused on the Red ones?
Although the Cruise control will only operate above 30mph I can select the cruise lever on the steering wheel and it changes the display to dash lines, with blank numbers as you'd expect. So I feel the top row of wires have the right connectivity to the dash display. Hope this makes sense.
ABS sensors have arrived but it is freezing out there and I'm putting that task off until tomorrow, and the same with the CAN Bus gateway checks.
Kind regards.

 

[onefortheroad]

When mine was stuck in park I had to literally clear every error code before I could select a gear .

 

[Lozzar]

So would you say the sharp thump on top of the gear stick to release it is a myth? I can't bring myself to do it. I've seen videos where they are extracting the selector and sending it off to be "repaired" ££kerching££, no doubt because someone took a hammer to it, but they don't show that bit. You have to be back in park to start the engine so it's hardly a long term solution?? Just going to do some resistance checks on the new ABS sensors to see what a new sensor resistance should actually be? I'll post the value later (in case anyone is interested). If it is the Reluctance ring (dirty or cracked) that's definitely a fair weather task. The Irony of all this is that in the days running up to the new year I completed a self build garage project, specifically to house this 6M long and fairly wide monster to keep it dry through the winter. It was in the garage until the day in late January, decent weather, when I took it out. For the last 3 years I simply covered the car up on the drive. The Garage treat seems to have back fired!

 

[onefortheroad]

So would you say the sharp thump on top of the gear stick to release it is a myth? I can't bring myself to do it. I've seen videos where they are extracting the selector and sending it off to be "repaired" ££kerching££, no doubt because someone took a hammer to it, but they don't show that bit. You have to be back in park to start the engine so it's hardly a long term solution?? Just going to do some resistance checks on the new ABS sensors to see what a new sensor resistance should actually be? I'll post the value later (in case anyone is interested). If it is the Reluctance ring (dirty or cracked) that's definitely a fair weather task. The Irony of all this is that in the days running up to the new year I completed a self build garage project, specifically to house this 6M long and fairly wide monster to keep it dry through the winter. It was in the garage until the day in late January, decent weather, when I took it out. For the last 3 years I simply covered the car up on the drive. The Garage treat seems to have back fired!

No idea. My shifter is on the steering wheel.

 

[mattkh]

By the way, what parking brake system do you have on your car..?

 

[Lozzar]

It is a foot operated type. It's a Right handed car and the "Foot Brake" is operated by the Left foot, against the gearbox cover. I saw another tip on youtube where you press the Brakes hard to close the gap between the pads and the discs so the pedal doesn't need to travel too much. The front Pads that I've seen are in good order. I haven't examined the rear brakes yet.

 

[Lozzar]

Often I will only use the Park Gear to hold the car, especially if I'm storing it for a while. Not wanting the brakes to stick onto the discs.

 

[joderest]

Don't know if same, on some Mercedes there is a small cover to the rear of the selector, which when removed allows a pen (or something similar) to be inserted to release the selector, may be worth a google look.

 

[joderest]

also, does this model have the cable release from brake pedal ?
Not being cleaver, just read it somewhere in the past.

 

[Lozzar]

Info only. New (front) ABS Sensors Resistance measures 19.83 Ohms.