We are having problems with our brakes on our 2002 Caravan Sport, we took it the local Tire Shop we use for all of our maintenance they said the problem was with the ABS valve, the code they got was P020 ABS Pump Circuit, we had a problem with the brake pedal feeling mushy when braking harder than usual and the ABS light came on last Saturday night and we had not driven it again until today which was to the tire shop the ABS light was not on but brake did not feel like it was firm.

The mech said if the the valve was not functioning right that is why the brakes are not firm the from time to time becasue it's not opening an closing right.

Is there a way to get the parts we need to replace to the ABS Valve ourselves without going to the dealership for a rather large bill in the end, and if so how difficult is it to replace.

We found a place in Florida when we replaced our ECM without going through the dealer and saved over $700.00 2 years ago and it is still going strong.

 

Welcome to DF
Here is part of the dealer pdf file, if you need the rest.send me a pm and a email address and i'll send them along.
Symptom:
PUMP CIRCUIT FAILURE
When Monitored and Set Condition:
PUMP CIRCUIT FAILURE
When Monitored: Ignition on. The CAB commands the pump on at 20 km/h (12 mph) to
check its operation, if the brake switch is not applied. If the brake is applied, the test will
run at 40 km/h (25 mph). The CAB monitors pump voltage every 7 milliseconds.
Set Condition: The DTC is stored when the CAB detects: 1) Improper voltage decay after
the pump was turned off. 2) Pump not energized by the CAB, but voltage is present for 3.5
seconds. 3) Pump is turned on by the CAB, but without sufficient voltage to operate it.
POSSIBLE CAUSES
PUMP HARNESS DISCONNECTED
CAB - PUMP MOTOR RUNNING CONTINUOUSLY
ABS PUMP MOTOR INTERMITTENT DTC
GROUND CIRCUIT HIGH RESISTANCE
FUSED B(+) CIRCUIT OPEN
GROUND CIRCUIT OPEN
CAB - INTERNAL FAULT
CAB - SETTING FALSE CODE
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Turn the ignition on.
Monitor the pump motor for continuous operation.
Is the pump motor running continuously?
All
Yes ! Replace the Controller Anti-Lock Brake in accordance with the
Service Information. The vehicle must be driven at 25 km/h (15
mph) to extinguish the ABS indicator.
Perform ABS VERIFICATION TEST - VER 1.
No ! Go To 2
2 Turn the ignition on.
With the DRBIIIt, read DTC’s.
With the DRBIIIt, erase DTC’s.
Turn the ignition off.
Turn the ignition on.
With the DRBIIIt, actuate the ABS pump motor.
Did the Pump Motor operate when actuated?

 

MT, thanks for this. I am at this point and the pump runs.

I hooked up our scanner and watched pump voltage and at the indicated MPH, I would get 3.2 volts. One time I saw 12.56 volts, but I didn't note the conditions.

Another things is that I would randomly see 3.2 volts while driving. I could see no rhyme nor reason for when it would happen. The troubleshooting guide said that it monitors pump voltage every 7 milliseconds, so maybe because it happens so fast, the scanner doesn't catch it very often when graphing it?

The other thing that I noticed was that wheel speed would randomly spike to 88 MPH. It could be any wheel at any time, moving or stationary. The only time that it wouldn't do it was sitting with Key on, Engine off. It seemed that it happened more often when applying the brakes, but I'm not sure.

I check the big fuse and the small fuse for the ABS and the small fuse had some white, talcum powder-like corrosion around it, but the metal was clean. I hit it with some electrical contact cleaner anyway.

Do you have any suggestions?

The van is exhibiting no driving symptoms, only the ABS light coming on and going off randomly.