Front brake hose routing diagramDTC “c31” (p0705): gp switch circuit
malfunction
Detected condition and possible cause
Detected condition
Possible cause
No gear position switch voltage
Gp switch voltage is not within the following range.
Gp switch voltage > 0.6 V
Gp switch circuit open or short.
Gp switch malfunction.
...
Front brake master cylinder / brake lever disassembly and assembly
Refer to “front brake master cylinder assembly removal and installation” .
Disassembly
Remove the reservoir cap (1), plate (2), diaphragm
(3) and reservoir tank (4).
Remove the brake light switch (5) and brake lever
(6).
Remove the dust boot (7) and push rod (8).
  ...
Continuity check
Measure resistance across coupler “b” (between “a”
and “c” in figure).
If no continuity is indicated (infinity or over limit), the
circuit is open between terminals “a” and “c”.
Disconnect the coupler “b” and measure resistance
between couplers “a” and “b-1”.
If no continuity ...