- Hydraulic brake booster pump motor
- Hydraulic brake booster pump motor circuit
- Pressure switch (PH or PL)
| Last Modified: 7-3-2017 | 6.8:8.0.40 | Doc ID: RM000001A6O005X |
| Model Year Start: 2007 | Model: LX470 | Prod Date Range: [08/2006 - ] |
| Title: BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1252/52; Brake Booster Pump Motor on Time Abnormally Long; 2007 MY LX470 [08/2006 - ] | ||
|
DTC |
C1252/52 |
Brake Booster Pump Motor on Time Abnormally Long |
DESCRIPTION
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
C1252/52 |
After the ignition switch is turned ON, the power is supplied to the pump motor for more than 5 minutes. |
|
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
|
1. |
CHECK OPERATION OF BRAKE ACTUATOR PUMP MOTOR |
|
(a) Disconnect the A43 and A44 actuator connectors. (b) Connect the battery positive (+) lead to terminal 2 (BM1) or 3 (BM2) and battery negative (-) lead to terminal 1 (GND1) or 6 (GND2) of the brake actuator (pump motor). OK: Operation sound of pump motor should be heard. |
|
| OK |
|
|
|
2. |
CHECK WIRE HARNESS (BRAKE ACTUATOR - ABS MTR 1 RELAY AND ABS MTR 2 RELAY) |
| NG |
|
|
|
3. |
CHECK WIRE HARNESS (SKID CONTROL ECU ASSEMBLY - BRAKE ACTUATOR) |
| NG |
|
|
|
4. |
READ DATA LIST (PRESS SWITCH (PH) AND (PL)) |
(a) Check the DATA LIST for proper functioning of the hydraulic brake boost pressure switch (PH) and (PL).
(b) Depress the brake pedal more than 40 times with the ignition switch OFF. Then turn the ignition switch ON and check the pressure switch (PH) and (PL) condition.
Skid control ECU assembly:
|
Item |
Measurement Item/Range (Display) |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
PRESS HIGH |
HIGH Hydraulic brake boost pressure/ ON or OFF |
- |
- |
|
PRESS LOW |
LOW Hydraulic brake boost pressure/ ON or OFF |
- |
- |
HINT:
When pressure in power supply system is released, reaction force becomes light.
OK:
"OFF" turns to "ON"
| OK |
|
|
|
5. |
CHECK BRAKE BOOSTER PRESSURE SWITCH (PH) |
|
(a) Disconnect the A43 actuator connector. (b) With the ignition switch OFF, depress the brake pedal more than 40 times to decrease the accumulator pressure. HINT: When pressure in power supply system is released, reaction force becomes light. (c) Measure the resistance between terminal 3 (PH) and 5 (PHG) of the brake actuator connector. Standard resistance: 0.9 to 1.1 kΩ (d) Connect the A43 actuator connector. (e) Disconnect the A43 actuator connector after the ignition switch has been ON and the pump motor has stopped. (f) Measure the resistance between terminal 3 (PH) and 5 (PHG) of the brake actuator. Standard resistance: Below 1 Ω HINT: After inspection, connect the connector and clear the DTC. |
|
| NG |
|
|
|
6. |
CHECK BRAKE BOOSTER PRESSURE SWITCH (PL) |
|
(a) Disconnect the A44 actuator connector. (b) With the ignition switch OFF, depress the brake pedal more than 40 times to decrease the accumulator pressure. HINT: When pressure in power supply system is released, reaction force becomes light. (c) Measure the resistance between terminal 4 (PL) and 2 (PLG) of the brake actuator connector. Standard resistance: 5.1 to 6.3 kΩ (d) Connect the A44 actuator connector. (e) Disconnect the A44 actuator connector after the ignition switch has been ON and the pump motor has stopped. (f) Measure the resistance between terminal 4 (PL) and 2 (PLG) of the brake actuator. Standard resistance: 1.0 kΩ HINT: After inspection, connect the connector and clear the DTC. |
|
| NG |
|
|
|
7. |
CHECK WIRE HARNESS (SKID CONTROL ECU ASSEMBLY - BRAKE ACTUATOR (PRESSURE SWITCH)) |
| NG |
|
|
|
8. |
INSPECT RELAY (Marking: ABS MTR 1, ABS MTR 2) |
|
(a) Remove the ABS MTR 1 and ABS MTR 2 from the engine room relay block. (b) Measure the resistance of the relay. Standard resistance:
|
|
| NG |
|
|
|
9. |
CHECK WIRE HARNESS (SKID CONTROL ECU ASSEMBLY - ABS MTR 1 RELAY AND ABS MTR 2 RELAY) |
| NG |
|
| OK |
|
|
10. |
CHECK WIRE HARNESS (SKID CONTROL ECU ASSEMBLY - BRAKE ACTUATOR) |
| NG |
|
|
|
11. |
CHECK BRAKE ACTUATOR PUMP MOTOR |
(a)
Check the brake actuator pump motor
![2007 MY LX470 [08/2006 - ]; BRAKE: HYDRAULIC BRAKE BOOSTER: DISASSEMBLY+](../../../../stylegraphics/info.gif "2007 MY LX470 [08/2006 - ]; BRAKE: HYDRAULIC BRAKE BOOSTER: DISASSEMBLY+")
.
| NG |
|
| OK |
|
|
|