C1027
DTC C1027: ESP(R) OFF Switch Circuit Failure
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
1.
Was "Electronic Stability Program Check" performed?
YES -
Go to Step 2.
NO -
Go to (ESP) Check Electronic Stability Program Check.
2. Check ESP(R) OFF switch
Turn ignition switch to OFF position.
Remove ESP(R) OFF switch referring to ESP OFF Switch Removal and Installation ESP(R) OFF Switch Removal and Installation.
Check for proper connection at each terminal of ESP(R) OFF switch.
If OK, then check ESP(R) OFF switch referring to ESP OFF Switch Inspection ESP(R) OFF Switch Inspection.
Is it good condition?
YES -
Go to Step 3.
NO -
Replace ESP(R) OFF switch.
3. Check ESP(R) OFF switch circuit
Disconnect ESP(R) control module connector.
Check for proper connection to ESP(R) control module connector at "E08-30" terminal.
If OK, then check resistance between connector terminal "E08-30" and vehicle body ground.
Is resistance infinity?
YES -
Substitute a known-good ESP(R) hydraulic unit / control module assembly and recheck.
NO -
"GRN/YEL" wire circuit is shorted to ground.