ABS light and passenger seatbelt removal

[turbo8765]

Is there any reason why complete removal of the passenger side seat and seatbelt assy would cause the abs light to illuminate??

I removed the seatbelt motor/track and disconnected the two connectors which connect to the motor. Also removed the seat, and the portion of the passenger side seatbelt within the center console. Now the ABS light illuminates when driving and stays on.

I plugged the motor back in just to see if it would eliminate the light and it did not.

1g, awd, 5spd w/ abs

 

[toybreaker]

Did you remove the rear seat as well?

There's a yaw sensor/accelerometer for the abs system mounted to the rear seat center belt bracket.

The abs ecu looks for that sensor to provide information on whether the car is in a straight line (wheel speeds same) or cornering (wheel speeds slightly different), as well as information about the rate of decelleration. It then uses this information to downgrade the sensitivity of the system in slow speed operation, while turning, to prevent the system from being hyperactive at low speeds. (like turning into a parking lot while braking)

During slow speed, sharp turns the wheel speeds will vary considerably because the wheels travel a different distance as you turn. (The outer front wheel will travel considerably farther than the inside rear wheel) Without this sensor, the anti-lock system would be hopelessly oversensitive while turning at low speeds, (and would freak out poor aunt betty on the way to the beauty parlour.)

You can also have the anti lock lite come on when using some scanners/dataloggers, as the ecu will disable the antilock system when using the data connector. (on some models)

Please, report back as to what the problem is/was.

 

[turbo8765]

Thanks for your reply.

I did remove the rear seat as well. Initially I also removed the rear seat area "g force sensor" or yaw sensor. I have since reinstalled this sensor.

At this point the yaw sensor is installed and connected. Nothing is connected to the diagnostic connector. The passenger seat and rear seats are out. The passenger seatbelt assembly is removed entirely.

I removed and reconnected the large connector for the abs controller.

The abs light remains on. I read that if the light stays off when the car is started and hasn't yet moved, but then illuminates after 10 or 20 sec of drivng, that there is a problem with a wheel speed sensor. I removed all the wheels and examined all the wheel speed sensors, and they all are visually normal.

Hmmm.....

 

[turbo8765]

Will the pocketlogger return any codes related to the ABS system?? For example, a bad wheel speed sensor.

 

[jtmcinder]

No. The biggest pain RE Mitsu ABS is none of the inexpensive code-readers can give you any information. You need a MUT or a $2k Genesis device to read Mitsu ABS. Even the Snap-On can't read our ABS codes. Grrrr.

Get a shop manual or do a search for how to get the CEL to blink the code. Or make friends with the local Mitsu dealer. The place local to me wants $40 to read an ABS code.

- Jtoby