TM-96
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P1774 LOW COAST BRAKE SOLENOID
P1774 LOW COAST BRAKE SOLENOID
Description
INFOID:0000000006159393
• Low coast brake solenoid valve is turned “ON” or “OFF” by the TCM in response to signals sent from the
transmission range switch, output speed sensor and accelerator pedal position sensor (throttle position sen-
sor). Gears will then be shifted to the optimum position.
• This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunc-
tion such as control valve sticking, improper solenoid valve operation.
CONSULT-III Reference Value in Data Monitor Mode
INFOID:0000000006159394
On Board Diagnosis Logic
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• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P1774” with CONSULT-III or 7th judgment flicker without CONSULT-III is detected
under the following conditions.
- When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 2 is irregular during depressing accelerator pedal. (Other than during shift change)
- When TCM detects that relation between gear position and condition of ATF pressure switch 2 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible Cause
INFOID:0000000006159396
• Harness or connectors
(The solenoid and switch circuits are open or shorted.)
• Low coast brake solenoid valve
• ATF pressure switch 2
DTC Confirmation Procedure
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CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
Floor shift models:
SLCT LVR POSI: “1” or “2” position
GEAR: “1st” or “2nd” (LC/B ON/OFF)
Column shift models:
MANUAL MODE SW: ON
GEAR: “1st” or “2nd” (LC/B ON/OFF)
3. Perform step “2” again.
4. Turn ignition switch “OFF”, then perform step “1” to “3” again.
5. Check “SELF-DIAG RESULTS” mode for “TRANSMISSION” with CONSULT-III. If DTC (P1774) is
detected, refer to
TM-97, "Diagnosis Procedure"
.
If DTC (P1772) is detected, go to
TM-94, "Diagnosis Procedure"
.
Item name
Condition
Display value
ON OFF SOL
Low coast brake engaged. Refer to
TM-96
ON
Low coast brake disengaged. Refer to
TM-96
OFF
ATF PRES SW 2
Low coast brake engaged. Refer to
TM-96
ON
Low coast brake disengaged. Refer to
TM-96
OFF