Possible Helpful Hints and brake test
Thanks to www.reatta.net for the information
If the "System" fails, (RED light is on) you
still should have some, very, very limited stopping power, which
might be helped by pumping the Emergency pedal until hard and
continue to press the brake pedal as hard as you can! You can try
this in your driveway, if it slopes, by putting car in neutral,
turn key to off, pumping pedal until it gets hard as a rock,
coast down the driveway and attempt to stop (Be careful!).
If your yellow light is on (again, be careful) you can
test to see if the Anti-lock system is actually working by
simulating an EMERGENCY stop at a speed of 30 mph. If a wheel
tries to lock up or slide you will feel a chatter in the pedal
and it may even rise a little. If you feel no chatter your
Anti-lock is either not working or you haven't applied brakes
hard enough.
A "safer" check, as the yellow light cause
may be a failed Main Relay, would be to switch the Main and Pump
Relays and see if the light goes out. (in some cases, if the Main
Relay has failed, after switching, both lights may be on.) See
note re. intermittent relay failure!
If you apply your brakes and the red light comes on
but goes out in a short time, your PUMP has re-pressurized the
system but you may have a weak or failed Accumulator or other
problems!
CRT
DISPLAYS and CODES SET by the ECBM
The CRT (88 and 89 models) will display three messages
pertaining to the brake system.
1. Brake fluid low
2. Parking brake is on
3. Anti lock Brakes (initiated by low brake pressure)
Note: BRAKE TROUBLE CODES do not appear on the CRT nor
are they displayed when DIAGNOSTICS is selected and BCM selected.
BRAKE TROUBLE CODES are stored in the ALDL. (Assembly Line
Diagnostic Link) Codes (42 can be stored) are set by the ECBM and
retrieved by grounding or jumping pins in the ALDL Connector. The
codes stored refer to wheel sensors, the main valve or the inlet
and outlet valves. No codes are stored by conditions affecting
the pump/motor, the accumulator, the pressure switch or the fluid
level sensor.
The ALDL is located just to the right of the parking
brake release handle. Refer to the manual for procedures to
retrieve, read and interrupt these codes.
Take the Brake Test!
Giving your car the tests below will aid you in
Troubleshooting and help you determine the General Condition of
the Brakes. (Results of 30+ Reatta Systems are immediately
following Test 6. Compare your results and read interpretations
of Tests.) A can of DOT 3 Brake Fluid and a watch w/ a second
hand may be needed. If all Blowers and Radio are off, hood is
raised, you will be able to hear the Pump run w/ driver door
open.
1st Test: Start car, wait a few seconds after brake
lights go out for pump to run and stop. Count the number of full
pedal pumps it takes to turn on the yellow and red lights. How
many pumps____?
2nd Test: Climate control and radio off. Wait for
lights out, then a few seconds for pump to stop running, Key off.
Count the number of full pedal pumps it takes till the pedal gets
very hard. How many pumps____?
Note: Now is the time to check the fluid level in the
reservoir. Fill to line (Triangle).
3rd Test: Turn key on (don't start engine) Count the
seconds until the red light goes out and continue counting until
the pump stops running. Note also when yellow light goes out or
if it doesn't. Seconds till Red light goes off_____? Yellow
Light, same time?
4th Test: Total seconds till pump stops running____?
Test 5: Leave driver door open w/ hood raised. Turn
key on, don't start engine. Listen and identify the brake system
pump running. (under the hood, on the firewall, drivers side).
Wait until the pump stops running. Depress the brake pedal one or
more times until the pump starts to run. How many pumps_____? Try
this several times, letting the Pump recharge the system, between
tests.
Test 6 :The system should be fully pressurized ( key
on, lights out, pump no longer running) and you should have
filled reservoir to the fill line while the system was
Depressurized , as per Manual, prior to this test! Make a mark,
grease pencil, masking tape, whatever, exactly at the Reservoir
fluid level. Measure the distance between the fill line and this
mark.
Averages of previous systems tested
Test 1. 10
Test 2. 28
Test 3. 32
Test 4. 45-50
Test 5. 2 1/2 to 3
Test 6. 1/2 inch.
Conclusions of brake tests Results
If the Pressure Sensor is malfunctioning [shutting off
the Pump before full pressure is obtained] none of the tests are
valid!
Test 1. Two or three pumps to turn on RED light with
engine running may suggest a weak or failing ACCUMULATOR.
(Certainly the reserve pressure is LOW!)
Test 2. Few pumps to discharge system (key off) and
make the pedal hard may also suggest an ACCUMULATOR problem or
the system may not be building to the designed pressure, Possibly
Pressure Sensor malfunction.
Test 3. A prolonged time to recharge system (to Red
light out), Possible causes: faulty Pump Relay, weak pump.
Test 4. The elapsed time, if significantly shorter or
longer than the average, may w/ other results, pinpoint the
problem.
Test 5. Most systems w/ failing or failed Accumulators
give lower than average results. 1/2 or 1 pump!
Test 6. This is a new test but over 3/4 inch is a good
indicator of a failed Accumulator.
If the ACCUMULATOR has NOT lost it's charge, there
will be a slow down in the speed of the pump as it charges the
system. This slowdown is audible and occurs about 2/3 through the
pumping cycle. A system, w/an accumulator that HAS lost its
charge, will not provide the audible change in pump speed until
the pumping cycle has almost completed.
Complete failure and a suggestion to replace many components, should require a second opinion. A failed accumulator, followed by a failed pump motor or pump, or both, are within reason. The appropriate Relays should also be changed when replacing a component.
Standard Disclaimer
Use at your own risk. The authors and those associated at Brads Reatta homepage take no responsibility for any damage resulting from any of the comments, recommendations or other direction contained herein, either implied or expressly indicated.
Brake Test