Your Vehicle: 2009 Nissan-Datsun Altima V6-3.5L (VQ35DE)
 
Vehicle » A L L Diagnostic Trouble Codes ( DTC ) » Testing and Inspection » P Code Charts » P1805  
 
 
  P1805  
 

P1805 BRAKE SWITCH

Description
Brake switch signal is applied to the ECM via 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.

DTC Logic

DTC DETECTION LOGIC

  

DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE

  1. Turn ignition switch ON.
  2. Fully depress the brake pedal for at least 5 seconds.
  3. Erase the DTC.
  4. Check 1st trip DTC. Is 1st trip DTC detected?

YES >> Go to Diagnosis Procedure.
NO >> Inspection END

Diagnosis Procedure
1.CHECK STOP LAMP SWITCH CIRCUIT

  1. Turn ignition switch OFF.
  2. Check the stop lamp when depressing and releasing the brake pedal.

  

Is the Inspection result normal?
YES >> GO TO 4.
NO >> GO TO 2.
2.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

  1. Disconnect stop lamp switch harness connector.
  2. Check the voltage between stop lamp switch harness connector and ground.

  

  

Is the Inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.

  • Fuse block (J/B) connector E6
  • 10 A fuse (No. 7)
  • Harness for open or short between battery and stop lamp switch >> Repair open circuit, short to ground or short to power in harness or connectors.

4.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

  1. Disconnect stop lamp switch harness connector.
  2. Disconnect ECM harness connector.
  3. Check the continuity between stop lamp switch harness connector and ECM harness connector.

  

  1. Also check harness for short to ground and short to power. Is the Inspection result normal?

YES >> GO TO 6.
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.

  • Fuse block (J/B) connector E6
  • Harness for open or short between ECM and stop lamp switch >> Repair open circuit, short to ground or short to power in harness or connectors.

6.CHECK STOP LAMP SWITCH
Refer to Component Inspection (Stop Lamp Switch).
Is the Inspection result normal?
YES >> GO TO 7.
NO >> Replace stop lamp switch.
7.CHECK INTERMITTENT INCIDENT
Refer to See: Testing and Inspection\Initial Inspection and Diagnostic Overview\Service Information For Electrical Incident\Intermittent Incident.
>> Inspection END

Component Inspection (Stop Lamp Switch)
1.CHECK STOP LAMP SWITCH-I

  1. Turn ignition switch OFF.
  2. Disconnect stop lamp switch harness connector.
  3. Check harness continuity between stop lamp switch terminals under the following conditions.

  

  

Is the Inspection result normal?
YES >> Inspection END
NO >> GO TO 2.
2.CHECK STOP LAMP SWITCH-II

  1. Adjust stop lamp switch installation. Refer to .
  2. Check harness continuity between stop lamp switch terminals under the following conditions.

  

  

Is the Inspection result normal?
YES >> Inspection END
NO >> Replace stop lamp switch.