P1843

DTC P1843 ATF PRESSURE SWITCH 3

Description
Fail-safe function to detect input clutch solenoid valve condition.

On Board Diagnosis Logic
^ This is not an OBD-II self-diagnostic item.
^ Diagnostic trouble code "ATF PRES SW 3/CIRC" with CONSULT-II is detected, when TCM detects that actual gear ratio is normal, and relation between gear position and condition of ATF pressure switch 3 is irregular during depressing accelerator pedal. (Other than during shift change)

Possible Cause
^ ATF pressure switch 3
^ Harness or connectors (The switch circuit is open or shorted.)

DTC Confirmation Procedure

CAUTION: Always drive vehicle at a safe speed.

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.

After the repair, perform the following procedure to confirm the malfunction is eliminated.

WITH CONSULT-II





1. Start engine.
2. Accelerate vehicle to maintain the following condition.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: "D" position
Gear position: 3rd => 4th Gear (I/C ON/OFF)
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving conditions required for this test.
3. Perform step "2" again.
4. Turn ignition switch to "OFF" position, then perform step 1" to "3" again.
5. Check "SELF-DIAG RESULTS" mode for "A/T" with CONSULT-II. If DTC (P1843) is detected, go to "(P1843); Diagnostic Procedure" If DTC (P1752) is detected, go to "(P1752); Diagnostic Procedure"

AT-FPSW3-01:

Wiring Diagram - AT - FPSW3

Diagnostic Procedure
1. INPUT SIGNALS (WITH CONSULT-II)
With CONSULT-II





1. Start engine.
2. Select "TCM INPUT SIGNALS" or "MAIN SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-II.
3. Drive vehicle in the "D" position (3rd => 4th gear), and confirm the ON/OFF actuation of the "ATF PRES SW 3".
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.

2. DETECT MALFUNCTIONING ITEM
Check the following items.
1. Check disconnection or short-circuit in the harness between ATF pressure switch 3 (I/C) (SEL 3 or DATA BIT 1) and TCM.
2. Check the connector housing for missing, loosening, bending or falling down of any terminal.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. CHECK DTC
Perform DTC confirmation procedure.
OK or NG
OK >> INSPECTION END
NG >> GO TO 4.

4. CHECK TCM INSPECTION
1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> INSPECTION END
NG >> Repair or replace damaged parts.