P1805

P1805 Brake Switch

Description
Brake switch signal is applied to the ECM through the stop lamp switch when the brake pedal is depressed. This signal is used mainly to decrease the engine speed when the vehicle is being driven.

On Board Diagnosis Logic
The MIL will not illuminate for this diagnosis.

P1805:

FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.






DTC Confirmation Procedure

NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with SDT.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to [P1805 Brake Switch].

Diagnosis Procedure

Step 1-2:

Step 3-6:

Component Inspection

STOP LAMP SWITCH
1. Disconnect stop lamp switch harness connector.






2. Check continuity between stop lamp switch terminals 1 and 2 under the following conditions.






3. If NG, adjust stop lamp switch installation, refer to [Brake Pedal Inspection and Adjustment] Adjustments, and perform step 2 again.