Anti-skid service required - code ABS 0130

Cees Klumper · Post by **Cees Klumper** » 28 Jul 2021, 06:59

THis is on my 2002 S80 T6.

This code has been coming on. Explanation on my code reader is "Brake pressure sensor 1 signal too low". I replaced what is numbered '1' sensor, located underneath the brake master cylinder, with a new one but the code came back. I then swapped sensors numbers 1 and 2, hoping it's the other sensor that was defective (they are identical and the plugs also, so they could have become swapped sometime in the past - maybe). After a short drive yesterday the fault has not yet come back.

What is strange: when I am stationary, the code reader can read the datastreams. But when I get moving, I get an error message that it is not able to establish connection with the ECU.

Also, even before I replaced the sensor(s), the data stream was able to read the brake system pressure from both sensors just fine, and they were close together, ranging from about 0 or slightly below, (yes, now that I write that, it does occur to me that a - reading would probably be called 'too low' by the computer - effectively this would mean there is vacuum in the system) all the way to above 100 when I press the brake 'prety hard'. So will continue to watch to see if the code comes back. Should not be negative I guess.

My question: does anyone know whether, IF my problem turns out to be the error-prone ATE ABS controller, this is registered to my individual car, i.e. I can't swap it out for a different (used) unit, without having that programmed to the car by a dealer, OR having me swap out the EPROM on the control board from the old unit to the replacement one? Because I worry that the real problem lies in the controller and not so much the sensor.

Any other tips also much appreciated. The car is in France, and here any fault having to do with the braking system is an automatic 'fail' for the bi-annual safety etc inspection (MOT) that I just had done. I have two months to fix it! Thanks in advance.

Cees Klumper · Post by **Cees Klumper** » 30 Jul 2021, 03:37

Well after two more days of short trips I accumulated 40 miles without the code coming back, so this morning I went back to the MOT place, they checked it out and gave a 'pass'. Good for the next 2 years. Still worry that the fault will re-surface so still interested if anyone knows whether the ABS module is registered to the car or not, just in case I have to troubleshoot further.

Cees Klumper · Post by **Cees Klumper** » 31 Jul 2021, 09:53

More driving today, another 60 miles in various trips. Code still not back, so starting to think maybe replacing the sensor that is labelled '2' rather than '1' did fix the issue. Fingers crossed. Still interested in confirmation whether the ABS module is registered to the car or not, but it seems nobody here knows, or reads this thread.

Cees Klumper · Post by **Cees Klumper** » 08 Aug 2021, 00:52

Well code is coming back, intermittently, and usually disappearing upon restart. Friday did a 400 mile trip and it only came back after 350 miles. Will replace also the second pressure sensor since it could be starting to fail around the same time as the 1st. And remove the ECM to clean its contacts, that could be a cause as well, I suppose.

Cees Klumper · Post by **Cees Klumper** » 27 Aug 2021, 00:12

Almost 3 weeks later now and code has not come back. I have the second sensor in hand (thanks Skandix) but have waited to put it in as I am not looking forward to bleeding all four brake calipers for a third time. Fingers crossed replacing just the one sensor did fix the problem and that the second sensor will live a bit longer still.

One upside to this story is I definitely replaced all the brake fluid in the system, by having bled it twice over the course of this repair.

Post by **RickHaleParker** » 27 Aug 2021, 01:32

Check the wiring for shorts and opens.

BCM-0130 Possible source

Open-circuit in the wiring.
Wiring is short-circuited to ground or supply voltage.
Damaged pressure sensor.
Internal fault in the control module.

skg · Post by **skg** » 10 Dec 2024, 14:55

Apologies for bringing up an old thread, but I'd very much appreciate some additional insights in the topic and GREATLY appreciate any additional insights into helping me solve this persisting and highly annoying issue.

2004 xc90 here.

Besides the wires to the brake pressure sensors, are there other wires to test?

I have the same issue, as the OP, with codes from VIDA (2014d) being BCM-0130 / BCM-0133, which I believe are causing the "anti-skid" error message on the dash and failing the BCM calibration at the Brake Sensor element. Using a multimeter, I've tested the wiring for both brake pressure sensor sub-harnesses, from the sensors to the BCM main connector, and each sensor's harness of 3 wires has 5 volts, current, and ground. This makes me believe that the connectors from the BCM to the brake pressure sensors are ok.

I first replaced the brake pressure sensor with a new unit (from FCP Euro) to remediate code BCM-0130. (One xc90 owner said her "anti-skid" message went away after replacing both Brake Pressure Sensors and the master brake cylinder.)

I then tested the pressure for both brake pressure sensors and the test indicated both would immediately hit peak pressure but pressure decreased quickly even though the brake pedal was pressed and held. Since we'd already replaced one sensor with a new unit, we deduced the pressure drop pointed to the master cylinder, which we replaced with a new unit.

After bleeding the system, trouble code BCM-0130 still persists. Very frustrating and discouraging.

As for the BCM possibly being the issue, I have replaced the BCM with a BCM from another 2004 xc90, with the hypothesis that two, unique BCMs from the same model and model year would have a low probability of having the same defect around reading the brake pressure sensors incorrectly. It's possible, but how plausible is it?

With the above data, would anyone have a recommendation of what steps to take?

Post by **RickHaleParker** » 12 Dec 2024, 17:31

Check for shorts between the wires. With key off and the Ohms function on the multi-meter.

skg wrote: ↑10 Dec 2024, 14:55 each sensor's harness of 3 wires has 5 volts, current, and ground. This makes me believe that the connectors from the BCM to the brake pressure sensors are ok.

skg · Post by **skg** » 29 Dec 2024, 12:35

Thanks for the tip... will try this. I appreciate the input!

skg · Post by **skg** » 30 Dec 2024, 08:49

RickHaleParker wrote: ↑12 Dec 2024, 17:31 Check for shorts between the wires. With key off and the Ohms function on the multi-meter.

Hi Rick, to clarify your above suggestion, are you saying check for shorts between the brake pressure sensor connector pins... connecting pin #1 to #2, #1 to #3, #2 to #3? If yes, what would be an expected "normal" reading vs. an indicator of failure between the pins?

Or are you saying to check each BPS wire between the BPS connector and the main BCM connector where the BPS wires insert? Previously, we tested each wire from the BPS connector insert to corresponding BCM connector insert and received what we thought to be normal readings, but then again, this is my first Volvo and Volvo seems to do things a little differently sometimes. Maybe we're just not clear on what to test?

Thanks, very much, for your input!