5 replies to this topic

[Dylan720]

Hi all ive been having a couple issues latley my engine light was on turned out to be the cam position sensor ive had it replaced and the lights gone off the fuel pump went in it yesterday had it replaces today and after all that i was driving it today and eveything was fine then the abs ligbt came on while driving. It wont go off as soon as i start the car its on driving down the rd its on dont matter what speed im doing its on. Ive checked both fuses under the steering wheel cant see any relays for it there and cant see any relays or fuses under the hood for it so i wanna check the moduel make sure nothings come off. I cant seem to find the abd moduel for this model can someone tell me and let me know what to check besides connections ? Anyhelp would be great thanks.

[duncanm]

its that big alloy cube with all the brake lines going into it on the driver's side under the air intake.

 

There's a big multi-pin plug into the box.

[Dylan720]

Ok so i removed the neg battery cable pumped break pedal a few times plus held it down for a bit to male sure it was completley drained then unpluged and cleaned the abs moduel plug and left it all for an hour and put it all back together and it still has thr abs light im guessing it must br a sensor is there anyway to check them before replacing them.

[duncanm]

sensors are pretty robust, I think.

 

ABS module is pretty standalone  - sensors (one each wheel, and a central G sensor I think under the console) go straight to module, the brake switch goes into it and the ABS warning light comes back.

 

Check all the sensor to ABS module wiring - most likely place one of the sensor wires has been damaged is in the wheel wells where the wiring comes from the car body to the tone ring via the strut.

[RX25SE]

My guess is the wiring is OK. A common way the system works it it runs a 'self test' when the key is turned on, this makes sure the ABS module can 'see' the sensors hanging off the ends of the wires by checking the internal resistance of the sensor (continuity test).

If all is OK at this stage the ABS warning lamp is turned off. (the lamp should come on for a short time when the key is first turned on as a 'globe test')

 

Once the car starts moving, the sensors generate a signal. The module then check again, but this time for a valid signal (signal test) and if the signal look good the warning lamp is kept off.

 

 

 

In addition to what Duncan suggested, make sure the sensors are correctly mounted and there is no build up of muck on the tips of the sensors of on the Tone Wheels (the toothed wheel the runs under the sensor)

 

 

 

 

This is a generic description, so it might pay to research that the Subaru system works the same way.

[duncanm]

good point -- they're magnetic, and I know last time I looked at one, it was caked with random road crud