ABS Relays

The name of the relay that powers up the ABS ECU.I got it on the wiring diagram.
k39(protection relay)

ABS pump relay:
k100(pump motor relay)

ABS HCU solenoids relay:
y22(hydraulic modulator relay)

ECU pin number for wire that gives power to ABS ECU:
26(A)

ECU pin number for wire that controls relay for ABS:
1(B)

ECU pin number for wire that gives power to the ABS pump:
8(E)

ECU pin number for the wire that controls ABS pump relay:
2(H)

I got all the relay names and ECU pin number by using the wiring diagram and folowing it.

I used a oscilloscope to capture the waveform that shows both the controll circuit change and power switching.

I got this picture from:http://amirs4825.blogspot.com/2010/11/abs-relays.html

channel 1(the bottom one) is the controll circuit and channel 2(the top one) is the switching circuit.Point A is when the switching circuit turns on and goes from 0v to 12v.B is when the switch is open,this is when the switching circuit is open.Point c is when the control circuit has collapsed we ca also see a voltage spike at this point.Point E and D is when the pump has been turned on and off.

ABS pump relay waveform:
 had to get waveform of control circuit changes when relay turns on and the power switching on to power on the ABS pump.

To get this waveform I had to conect HC11 to power 85 and hotwire 30 shows the top one and 85 is the bottom one.On chanel B(the top one.)were it goes up is were its turned on and the top part from corner to corner shows that ECU is earth trigerd.Then at the second time when it goes up again is when the key is turned off.Then at the bottom one where it goes up is when ABS pump spiking.When down again is when signal switched.

ABS self test:
To make sure all the components in the ABS system are workin it has to do a selftest,it does this test when we turn the ignition on.It has a 12v supply.The ABS control module checks most of the components in the circuit exept for the components it can not check like the wheel speed sensors wich cannot be checked unless the car is moving.If the ABS controll module does not triger the failsafe relay the ABS light on the dash will not go of.This wil indicate that the module has found a fault in the ABS system.

Create a fault:
I did this by slowing down a wheel speed sensor while aplying the brakes.I did this by using a piece of plastic pipe and pressing on wheel while braking.The modulator can see this because one wheel slowin down faster than the rest of them so senses tha it is going to lock up.It stops this from hapenning by opening the inlet valve with a solenoid so there is no more presure being applied.

ABS solenoid actuated:


On this diagram we can see all the pin number and solenoid names.for example were it says solenoid LF means lef front solenoid then the wire that goes down to circile tha say 1B is the pin number for that solenoid.
Left front solenoid:
pin:1B
right front solenoid:
pin:1C
Left rear:
pin:1D
right rear:
pin:1A

I got the waveform for this on oscilloscope for the left front solenoid.

It is a solenoid therefore it looks like an injectors waveform they also share some of the same qaulitys.