Brake On/Off (Boo) Switch - Mazda B-Series 1997 Workshop Manual

TEST PINS LOCATED ON
BREAKOUT BOX.
ON-BOARD DIAGNOSIS SYSTEM
FT
Diagnostic tr
uble
code No.
P0703, PI703
Symptom
BRAKE ONlOFF (BOO)
SWITCH
- -
BOO switch input voltage high or low, or out of self-test range.
ACTION
Go to step 3.
Rerun KOER self-test.
Rerun KOEO self-test.
STEP
1
2
3
4
5
6
7
8
9
10
MF1845-C
INSPECTION
Note: This test is for DTC PO703 only. For other DTC,
go to step 2.
Was brake pedal pressed and released during KOER?
Was brake pedal pressed during KOEO self-test?
BRAKE
ON/OFF
SWITCH
0
BOO
SIG
-
LG 4
TEST PIN 92
TO ACCESSORIES
4
STOPLIGHT
Yes
No
Yes
Key ON and check stoplamp operation.
No
Yes
Go to next step.
Go to next step.
No
Stoplamps never on:: Go to step 5.
Stoplamps always on: Go to step 7.
Replace PCM.
Go to step
10.
Repair open in BOO c:ircuit between PCM and
BOO connection to st~splamp circuit.
Go to step 10.
Go to next step.
Repair open B+
circuit
to
switch.
Go to step 10.
Repair open circuit between BOO and
Key OFF. Yes
Check for damaged or pushed out pins, corrosion or loose
wire. Repair or replace as necessary.
Install breakout box, leave PCM disconnected.
Does voltage between BOO test pin 92 and PWR GND
test pin 76 or 77 at breakout box cycle while pressing and
releasing brake?
Key OFF. Disconnect BOO switch.
Is voltage between switch and chassis ground greater than
10 volts?
Is resistance of BOO switch less than 5.0 ohms while
i -
No
Yes
No
Yes
pressing brake pedal?
Key OFF.
Disconnect BOO switch connector.
ground.
- - -
No Replace BOO switch.
Go to step 10.
-
Yes
,
Go to next step.
,
I
If BOO switch is properly installed, replace
BOO.
Go to next step.
Replace PCM and go to step 10.
Repair short to power in BOOIstoplamp
circuit.
Go to next step.
Repair short in accessories.
Go to next step.
Key ON, engine off. No
Are stoplamps still on?
- -
Key OFF. Yes
Leave BOO switch connector tlisconnected.
Disconnect PCM. Key ON.
PO
Are stoplamps still on?
Perform After Repair Procedure to ensure customer's concern has been resolved.
Key OFF.
Leave BOO and PCM connector disconnected.
Disconnect shiftlock actuator, cruise control module, ABS
module and GEM. Key ON.
Are lamps still on?
Yes
No