1996 CRX ABS Light and Diagnosis.... help! :)

[astormsau]

Hi everyone
I have an ABS problem and was hoping for some aassistance.

My car is a 1996 CRX (late model del sol)

Started the car on new years day after a trip from Melb over to Adelaide in the days before, very hot weather... The ABS light came on, drove down the road 20 mins and stopped to get some fuel, the ABS light went off and was off for the rest of the 2hr drive I did that day. Next few days the same situation, light would come on, i'd stop the car and it would go off, when it was off I tried slamming the breaks and the ABS would actually work... the next morning the light would be on again. Finally after 4 days it got to the point where the light was always on and wouldnt go out.

Took the car to Honda and almost fell over with a quote for nearly 6 grand for new:

ABS modulator $3800
ABS accumulator $500
ABS pump $1500

I tried some diagnosis of my own after reading around on the forums, shorted out the diag connector under the glove box, I am getting code 1 with my ABS light with is ABS pump over-run. I have tried the following:

1. checking all fuses in the ABS fuse box under bonnet - all fine
2. checking grounding to the ABS computer accessed in the boot of the vehicle mounted to firewall - appeaers ok
3. using contact cleaner to clean all relays and fuses in the ABS fuse box and all orange connectors to modulator unit and ABS fuse box connectors - nothing seemed dirty or corroded
4. check wheel speed sensors to confirm that they are showing voltage when we spin the wheels and inspect wheel speed sensors for any damage - they show small amount of voltage when wheels spun.
5. check fluid in both brake reservoir and fluid reservoir on top of ABS modulator - both full.
6. short connects for ABS relay to test pump operation - pump makes a normal pump-like noise.
7. start car and check that ABS relay clicks to activate pump - ABS relay clicks, pump turns on, runs for about 25 seconds and then relay clicks again and pump turns off.
8. checked that the orange ABS pump connector has voltage when the car is turned on and started.
9. Pull the ECU fuse to reset ECU.
10. Disconnect the ABS computer to reset ABS light although i am aware that the system retests itself when the car is turned on.

There is only 1 strange thing I can find...

I disconnected the pressure switch (orange connector with orange and grey wires leading into it) which is attached to the top of the modulator. I put a multimeter on it to check the switch. The switch was open when the car was turned off, i started the car and the pump ran for 25 odd seconds and then turned off (checked this by verifying the relay clicked on and then off) when the pump turned off the switch was still showing as open.....

So my questions are:

1. is the pressure switch available as a part ?
2. is the abs pump removable on this model?
3. are there any other tests I could do or any other suggestions to help with this?

My car is a 96 with low km's on it, and in good condition, seems a shame not to have ABS working and at $6000 its hardly worth repairing. I am in Melbourne, if someone could recommend an expert with these things it would be great... as im sure this repair can be alot cheaper than 6k...

[ECU-MAN]

pressure switch could be the problem,

dont tun the pump for to long as you can over presureize the system and to more damage.

when you hear the pump realy struggle then you stop priming it, the swich should close circuit when the optimum pressure is reached.

You would have to call honda to find out if its available as a spare part or if you have to pruchase a complete pump.

good luck

[astormsau]

pressure switch could be the problem,

dont tun the pump for to long as you can over presureize the system and to more damage.

when you hear the pump realy struggle then you stop priming it, the swich should close circuit when the optimum pressure is reached.

You would have to call honda to find out if its available as a spare part or if you have to pruchase a complete pump.

good luck

I was doing some testing tonight, the pump doesnt actually labour when the car is started and the pump is activated. So I think the issue is that the pump is not actually building preassure in the accumulator as it runs freely and doesnt slow down or make sounds as if its labouring, as it should.

Any ideas..?

[ECU-MAN]

pump may have died,

it should start to labour even if the acuumulator is leaking. if its runns freely and effortlessly then the drive to the pump from the motor may have failed.

remove the pump and see if you can dismantle it.

[astormsau]

pump may have died,

it should start to labour even if the acuumulator is leaking. if its runns freely and effortlessly then the drive to the pump from the motor may have failed.

remove the pump and see if you can dismantle it.

thanks for your advice so far ECU-MAN
i believe the pump is removable from the modulator on some CRX's and not on others... do you know anything about this? mine is the post 96 model with airbags and updated dash,etc... do you know if this would have a removable pump?

Thanks

[ECU-MAN]

IF I remember correctly, the pump was seperate to the modulator

[astormsau]

ECU MAn
did you used to own a red crx? which you sold about 15 months ago?

[ECU-MAN]

sure did