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DSC light illuminating with all of the various iterations, i.e; ABS, BRAKE and (later) Tire Control Inactive began to occur a few
days ago. First step was to check each of the wheel speed sensors and their wiring by verifying each of the each sensors' diode
biasing (forward and rear), using a DVOM with diode testing functionality, at the DSC/ABS connector.

First, get a small length of phone cable that uses solid copper wire in 20 gauge, to closely match the male pins present in the
module connector. You will need at least two of the encased wires, with each about 3-4 inches. Strip one-half inch on one end
and approximately one inch on the other (This end will be used to wrap around the probe end on each of the DVOM leads). If
you have a set of leads with alligator clips, just strip one-half inch on each end.

The pin-outs for each sensor at this connector are as follows;
- Right front: pins 15 and 16
- Left front: pins 28 and 12
- Right rear: pins 30 and 31
- Left rear: pins 13 and 29

With DVOM selector set to the diode test mode, insert each of the 20 gauge wires into the two pins for each sensor, as per
above. You should see 1.7 to 1.9 V (forward bias)in one direction and then reversing the leads should yield 0L (Open) (the
reverse biasing. This will test not only the sensor in question, but also the wiring. In my case, all sensors tested OK.
In the event you find a failure with one of the sensors, disconnect the sensor in question and repeat the test for the sensor
itself. If okay, you have a wire fault from the DSC/ABS connector to the sensor connector. If the test at the sensor connector
fails, then that sensor needs replacement and you have likely found the source of the problem (wheel speed sensors are the
primary source of problem).

Though I found no defects with any of the four wheel speed sensors, I removed each of the sensors for cleaning. The rear
sensors in particular were quite dirty, with fine metal particles attached to the ends of each sensor (internal magnet). After
cleaning, I applied a coating of silicone paste at the end of each.

During my trouble shooting, I was able to disconnect the DSC/ABS connector (with a cold engine compartment), reinstall
connector, start engine with no DSC light. Using a heat gun, I then heated the DSC/ABS and hydraulic module. Within a
few minutes, the DSC light would appear, pointing to a possible failed solder joint or individual component.

With all wheel speed senors testing normally, remove the entire air filter box, followed by all six (6) of the Torx screws that
hold the DSC/ABS onto the hydraulic module. Carefully slide out the DSC/ABS module. You will note that there are ten(10)
soldered terminals that are the assembly connections between the two main internal components.

Given the fact there was nothing to lose, I re-soldered each of the ten terminals, using a Rosin Activated (RA) Flux applied
first, then added the rosin-cored solder. After cleaning the residual flux with acetone, I then re-installed the DSC/ABS module.
Before installing the DSC/ABS module connector, thoroughly clean both the male and female terminals with aerosol electronics
contact cleaner and dry with compressed air.

System is now operating normally after 500 miles.

This is certainly no "all-inclusive" repair for all DSC module faults, however it did work here and I would certainly recommend
it as a first-step, before sending your module off for repair (or purchasing a new unit).

Regards,
Alan
 

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I am having the same issues my question is did it take 500 miles for the unit to reset or did you have to have the ABS module re coded by dealership.
 

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I am having the same issues my question is did it take 500 miles for the unit to reset or did you have to have the ABS module re coded by dealership.
Since he repaired the module, no need to recode. It is already coded to the car.

I believe it resets once fixed, he is telling us that after 500 miles, or 3 years, whichever comes first, the problem has not returned.

Regards,
Jerry
 
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Cleaned All Sensors Last Night And Did The Module Repair Just Incase Checked Secret Menu For Wheels Speed To See If One Was Working Etc But Neither Appear To Work Via The Secret Menu, Scanner Isnt Peak Its Just Showing Speed Sensor A Fault.. Going To Test Later Today..
 

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if any speed sensor fails the whole system is down, whether to front speed sensor or rear wheel speed sensor is that correct? I only say that because I assume that via the secret menu if I had a rear speed sensor that was bad I would be able to tell which one it is via the menu
 

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if any speed sensor fails the whole system is down, whether to front speed sensor or rear wheel speed sensor is that correct? I only say that because I assume that via the secret menu if I had a rear speed sensor that was bad I would be able to tell which one it is via the menu
That' my understanding. But sometimes you can isolate a sensor by other functions.. It seems that one of the sensors is connected to a wheel that handles cruise control (RR?). So if no cruise control, for example, you can focus on a particular corner of the car. I think another is the speedo for one of the fronts (LF?).

Regards,
Jerry
 

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Forgive me if this is dumb or over simplified but if you're driving and you get this array of lights and other things such as no speedo, no cruise control, etc. Would a valid test be to turn the car off and let it reset, then turn the car back on without moving or rolling. If all lights come back on would it be safe to assume that it is the ABS/DSC unit probably due to the heat of the engine? If I'm not rolling then there is nothing to trigger the wheel sensors to send a fault right?
 

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Almost ready to do this fix on my ABS module but let me ask something first.

When I start the car in the morning, the trifecta lights will stay on until the car is drive forward. Then they'll not light up again until the car is off and on again.

My point is that my module don't seems to be affected by temperature, I can drive for more than one hour without the trifecta ever turning on.

But, I can drive for two minutes, turn off the car and back on, and they there are, the lights again.

Same thing has been happening for almost a year now.

Speed sensors were replaced a year ago when the lights start appearing. It was a temporary cure because now I'm still stuck with the problem.

Any input is appreciated.
 

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Forgive me if this is dumb or over simplified but if you're driving and you get this array of lights and other things such as no speedo, no cruise control, etc. Would a valid test be to turn the car off and let it reset, then turn the car back on without moving or rolling. If all lights come back on would it be safe to assume that it is the ABS/DSC unit probably due to the heat of the engine? If I'm not rolling then there is nothing to trigger the wheel sensors to send a fault right?
You may be right if the problem is the wheel sensor is sending an implausible signal when moving, but it could also have failed open circuit or shorted which would be detectable as soon as the key was turned on.
 
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