DOOR LOCK AND POWER WINDOWS — TROUBLE DIAGNOSIS — Diagnostic Procedure 4
BF-21flowchartUnverifiedPage-code 'BF-21' is not visible on this scan (bottom margin obscured by scan-edge black streak). Inferred from the BF-20 → BF-22 continuation chain. Up/Down voltages of 12V vs 5V at terminal 12/28 reflect the encoded data signal between master and sub switches.
Diagnostic Procedure 4
NOTE
SYMPTOM: Passenger side power window cannot be operated by driver's side main switch but can be operated by passenger's side switch.
Diagnostic Procedure 4 — main-switch → passenger-side data path
1
A — CHECK DRIVER SIDE MAIN SWITCH OUTPUT VOLTAGE.
1) Turn on ignition switch with connector (D6) connected to main switch.
2) Check output voltage at terminals (12) while operating main switch.
N.G.
Replace main switch.
O.K.
2
B — SHORT-CIRCUIT CHECK BETWEEN DRIVER SIDE AND PASSENGER SIDE SWITCHES.
1) Turn off ignition switch.
2) Disconnect 12-pin connector (D6) from driver side switch.
3) Check resistance between terminal (12) and body ground. CONTINUITY SHOULD NOT EXIST.
N.G.
Repair harness.
O.K.
3
C — CHECK PASSENGER SIDE SWITCH INPUT VOLTAGE.
1) Connect driver side switch connector (D6).
2) Disconnect passenger side switch connector (D14).
3) Turn on ignition switch.
4) Check input voltage at terminal (28) while operating driver side switch.
N.G.
Repair harness between driver side and passenger side switch.
O.K.
CHECK PASSENGER SIDE SWITCH AND REPLACE IF NECESSARY.
Test A — main switch output voltage at terminal 12
12
Terminal (−)GND
Switch OperationUp
VoltageApprox. 12V
12
Terminal (−)GND
Switch OperationDown
VoltageApprox. 5V
Test C — passenger-side switch input voltage at terminal 28
28
Terminal (−)GND
Switch OperationUp
VoltageApprox. 12V
28
Terminal (−)GND
Switch OperationDown
VoltageApprox. 5V