Electric Vacuum Pump System Acura RDX I

Scheme 87

System Indicator

This system has an electric vacuum pump system indicator (A).

1. When the system detects a problem, the electric vacuum pump system indicator stays on.
2. When the system is normal, the electric vacuum pump system indicator comes on after turning the ignition switch ON (II), then it goes off under these conditions. Before starting the engine. After starting the engine. Pressing the brake pedal for the first time after starting the engine.

Scheme 88

Diagnostic Trouble Code (DTC)

1. The memory can hold any number of DTCs. However, when the same DTC is detected more than once, the more recent DTC is written over the earlier one. Therefore, when the same problem is detected repeatedly, it is memorized as a single DTC.
2. The DTCs are indicated in the order they occur.
3. The DTCs are memorized in the PCM.
4. The electric vacuum pump system DTCs are shown independently, and are treated as additional internal data by the PCM. Therefore, the electrical vacuum pump system DTCs are canceled by disconnecting the battery.

Self-diagnosis

1. Self-diagnosis can be classified into two categories: Initial diagnosis: Done when the ignition switch is turned ON (II), and until the electric vacuum pump system indicator goes off. Regular diagnosis: Done right after the initial diagnosis, until the ignition switch is turned OFF.
2. When the system detects a problem, the system shifts to a fail-safe mode.

Pump Motor

The electric vacuum pump operates as needed. You can hear the motor function at times, this is normal. The pump motor operates under these conditions

1. The system detects if the brake booster vacuum becomes low while the engine is running.
2. After cold starting the engine, or when the outside temperature is very cool.
3. At high altitude.

The pump motor turns off when the system detects the brake booster vacuum is sufficient. If the system detects a fault, it shifts to fail-safe mode, and turns on the electric vacuum pump system indicator.

Relationship of the Fuel and Emissions Systems

The electric vacuum pump system is a part of the brake systems. Operation relies on information from sensors in the fuel and emission systems. Review the general troubleshooting in the fuel and emissions systems section (see GENERAL TROUBLESHOOTING INFORMATION ).

How to Troubleshoot DTCs

The troubleshooting procedures assume that the cause of the problem is still present and the electric vacuum pump system indicator is still on. Following the procedure when the electric vacuum pump system indicator does not come on can result in incorrect diagnosis.

When a client has driven the vehicle abnormally, these DTCs might be stored

1. DTC P15BC: Drive the vehicle and apply/release the brake pedal repeatedly for 1 minute or more.
2. DTC P0571: Both the brake pedal and the accelerator pedal are pressed at the same time for 5 minutes, and vehicle speed is 12 mph (20 km/h) or more. Stop the vehicle speed from 24 mph (40 km/h) without pressing brake pedal (using only parking brake etc.) continuously 3 times or more.

1. Ask the client about the conditions when the problem occurred and the electric vacuum pump system indicator came on, such as during braking, acceleration when vehicle was travelling at a certain speed, etc.
2. When the electric vacuum pump system indicator does not come on during the test-drive, but troubleshooting is done based on the DTC, check for loose connectors, poor contact of the terminals, etc.
3. After troubleshooting or repairs are done, clear the DTCs, and test-drive the vehicle under the same conditions as when the DTC was originally set. Make sure the electric vacuum pump system indicator does not come on.
4. Check for DTCs in other systems that are connected via the F-CAN. If there are DTCs that are related to the F-CAN, the most likely cause was that the ignition switch was turned ON (II) while the PCM connectors were disconnected.

Intermittent Failures

The term "intermittent failure" means a system may have had a failure, but it checks OK now. If the electric vacuum pump system indicator on the instrument panel does not come on, check for poor connections or loose terminals at all connectors related to the circuit that you are troubleshooting. If the indicators were on but then went out, the original problem may have been intermittent.

Scheme 89

1. If the electric vacuum pump system indicator stays on, connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
2. Turn the ignition switch ON (II).
3. Make sure the HDS communicates with the PCM. If it doesn't, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ).
4. Check the diagnostic trouble code (DTC) and note it. Also check the on-board snapshot data, and download any data found. Then refer to the indicated DTC's troubleshooting, and begin the appropriate troubleshooting procedure. NOTE: The HDS can read the DTC, freeze data, snapshot, current data, and other system data. For specific operations, refer to the Help menu that came with the HDS.

How to Retrieve DTCs

1. With the ignition switch OFF, connect the HDS to the data link connector (DLC) under the driver's side of the dashboard.
2. Turn the ignition switch ON (II).
3. Make sure the HDS communicates with the PCM. If it doesn't, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ).
4. Follow the prompts on the HDS to display the DTC(s) on the screen. After determining the DTC, refer to the «DTC TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) .
5. Turn the ignition switch OFF.

How to Clear DTCs

Note. Check for fuel and emissions systems DTCs and write down the codes indicated.

1. With the ignition switch OFF, connect the HDS to the data link connector (DLC) under the driver's side of the dashboard.
2. Turn the ignition switch ON (II).
3. Make sure the HDS communicates with the PCM. If it doesn't, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ).
4. Clear the DTC(s) by following the screen prompts on the HDS.
5. Turn the ignition switch OFF.

DTC Troubleshooting Index

DTC TROUBLESHOOTING CHART

Symptom Troubleshooting Index

When the vehicle has one of these symptoms, check for a diagnostic trouble code (DTC) with the HDS. If there is no DTC, do the diagnostic procedure for the symptom, in the sequence listed, until you find the cause.

SYMPTOM TROUBLESHOOTING CHART

System Requirement

Due to the addition of the turbocharger, the intake manifold vacuum can be reduced affecting the brake boost. To compensate for this loss of vacuum, the electric vacuum pump is required.

1. During cold engine starting; the fuel and emission system retards the ignition timing to help heat up the catalytic converter and the turbocharger with high exhaust temperature. In this case, the vacuum pressure in the intake manifold is reduced, especially in high altitude areas where low atmospheric density conditions create a long warm up condition.
2. When the turbocharger system turbo charges the intake air, the intake manifold vacuum is reduced.

System Control

The electric vacuum pump controls the target vacuum of the brake booster compared to atmosphere pressure.

Scheme 90

System Electrical Structure

The system has a brake booster pressure sensor, an electric vacuum pump, a electric vacuum pump system indicator in the gauge control module, and the PCM with fuel and emission systems sensors.

Scheme 91

System Air Flow

The brake system includes these components: A brake booster pressure sensor, an electric vacuum pump with a filter, a check valve (vacuum pump), and a 3-way joint on the conventional brake system booster vacuum hoses.

Scheme 92

The electric vacuum pump has a motor and a rotor with five sliding vanes. The motor rotates the rotor, which generates the vacuum.

The motor function is controlled by the PCM.

Brake Booster Pressure Sensor

The brake booster pressure sensor converts brake booster absolute pressure into electrical signals to the PCM.

Scheme 93

CONNECTOR TERMINALS REFERENCE

Scheme 94

CONNECTOR TERMINALS REFERENCE

Scheme 95

CONNECTOR TERMINALS REFERENCE

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1. Turn the ignition switch ON (II).
2. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS. Is it between 0.19 and 4.8 V? YES -Intermittent failure, the system is OK at this time. Check for loose terminals between the brake booster pressure sensor 3P connector, and PCM connector A (44P)/B (44P). Refer to intermittent failures troubleshooting (see «INTERMITTENT FAILURES»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__intermittent-failures) ). NO -If 0.19 V or less is indicated, go to step 3 . If 4.8 V or more is indicated, go to step 14 .
3. Turn the ignition switch to LOCK (O).
4. Disconnect the brake booster pressure sensor 3P connector.
5. Turn the ignition switch ON (II).
6. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS. Is 0.19 V or less indicated? YES -Go to step 7 . NO -Go to step 12 .
7. Turn the ignition switch to LOCK (O).
8. Short the SCS line with the HDS.
9. Disconnect PCM connector B (44P).
10. Check for continuity between body ground and brake booster pressure sensor 3P connector terminal No. 2. Is there continuity? YES -Repair short to body ground in the wire between the brake booster pressure sensor and the PCM. NO -Check for loose terminals in the brake booster pressure sensor 3P connector and PCM connector A (44P)/B (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ).
11. Turn the ignition switch to ON (II).
12. Measure voltage between brake booster pressure sensor 3P connector terminals No. 1 and No. 3. Is there about 5 V? YES -Replace the brake booster pressure sensor (see «BRAKE BOOSTER PRESSURE SENSOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ). NO -Go to step 13 .
13. Measure voltage between body ground and brake booster pressure sensor 3P connector terminal No. 1. Is there 0.1 V or less? YES -Repair open in the wire between the brake booster pressure sensor and the PCM. NO -Check for loose terminals in the brake booster pressure sensor 3P connector and PCM connector A (44P)/B (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ).
14. Turn the ignition switch to LOCK (O).
15. Disconnect the brake booster pressure sensor 3P connector.
16. Connect brake booster pressure sensor 3P connector terminals No. 2 and No. 3 with a jumper wire.
17. Turn the ignition switch ON (II).
18. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS. Is 4.8 V or more indicated? YES -Go to step 19 . NO -Replace the brake booster pressure sensor (see «BRAKE BOOSTER PRESSURE SENSOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ).
19. Disconnect the jumper wire from the brake booster pressure sensor.
20. Measure voltage between body ground and brake booster pressure sensor 3P connector terminal No. 2. Is there about 5 V? YES -Repair open in the wire (SG6 line) between the brake booster pressure sensor and the PCM. NO -Go to step 21 .
21. Turn the ignition switch OFF.
22. Short the SCS line with the HDS.
23. Disconnect PCM connector B (44P).
24. Check for continuity between brake booster pressure sensor 3P connector terminal No. 2 and PCM connector B (44P) terminal No. 5. Is there continuity? YES -Check for loose terminals in the brake booster pressure sensor 3P connector and PCM connector A (44P)/B (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). NO -Repair open in the wire between the brake booster pressure sensor and the PCM.

DTC P0556: Brake Booster Pressure Sensor Circuit Range/Performance Problem

Special Tools Required

Vacuum pump/gauge, 0-30 in. Hg, Snap-on YA4000A or equivalent, commercially available

Note. If DTC P0556 is stored at the same time as DTC P0571, troubleshoot DTC P0571 first, then recheck for DTC P0556.

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1. Turn the ignition switch OFF.
2. Disconnect the vacuum hose (A) for the brake booster pressure sensor (B) from the brake booster, and connect a vacuum pump/gauge, 0-30 in.Hg, to the brake booster pressure sensor hose.
3. Turn the ignition switch ON (II).
4. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS before and after applying vacuum to the hose using the vacuum pump/gauge. Does the indicated value change? YES -Go to step 5 . NO -Replace the brake booster pressure sensor (see «BRAKE BOOSTER PRESSURE SENSOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ).
5. Turn the ignition switch OFF.
6. Check for vacuum leaks or clogging at these parts: Brake booster pressure sensor hose. Brake booster vacuum hoses and their joints. Check valve (intake manifold). Check valve (vacuum pump) and filter. Brake booster. Are the parts OK? YES -Go to step 7 . NO -Repair or replace the leaking or clogged part(s).
7. Check the brake pedal position switch signal circuit (see «BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system) ). Is the circuit OK? YES -Go to step 8 . NO -Troubleshoot the brake pedal position switch signal circuit.
8. Reconnect the vacuum hose on the brake booster pressure sensor to the brake booster.
9. Turn the ignition switch ON (II).
10. Note the BRAKE BOOSTER PRESSURE in the DATA LIST with the HDS.
11. Turn the ignition switch LOCK (O).
12. Do the battery terminal disconnection procedure (see «DISCONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__disconnection) , and wait several seconds.
13. Do the battery terminal reconnection procedure (see «RECONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__reconnection) , then do this procedure after the troubleshooting
14. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS when the electric vacuum pump runs while you turn the ignition switch ON (II). Do not start the engine. Does the indicated value change when the motor runs? YES -Intermittent failure, the system is OK at this time. Check for loose terminals between the electric vacuum pump relay 2 4P connector, the electric vacuum pump 2P connector, the brake pedal position switch 4P connector, and PCM connector A (44P). Refer to intermittent failures troubleshooting (see «INTERMITTENT FAILURES»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__intermittent-failures) ). NO -If the pump does not run, go to step 15 . If the pump runs, turn the ignition switch OFF, then repeat steps 12 to 14 again. If you still get the same brake booster pressure sensor value, replace the electric vacuum pump (see «ELECTRIC VACUUM PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ).
15. Turn the ignition switch to LOCK (0).
16. Check the connection and pin fit of the electric vacuum pump 2P connector. Is the connector properly connected? YES -Go to step 17 . NO -Connect the electric vacuum pump 2P connector properly. If necessary, repair or replace the connector.
17. Remove electric vacuum pump relay 2, and check it (see «POWER RELAY TEST»(/acura/rdx/i-2006-2009/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES -Go to step 18 . NO -Replace electric vacuum pump relay 2.
18. Remove the No. 17 (15 A) fuse from the under-hood fuse/relay box.
19. Remove the No. 31 (7.5 A) fuse from the auxiliary under-hood fuse/relay box.
20. Check for continuity between electric vacuum pump relay 2 terminal No. 2 and No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box terminal No. 1. Is there continuity? YES -Go to step 21 . NO -Repair open in the wire between electric vacuum pump relay 2 and the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box.
21. Remove electric vacuum pump relay 1.
22. Install the No. 17 (15 A) fuse in the under-hood fuse/relay box.
23. Connect electric vacuum pump relay 2 connector terminals No. 1 and No. 2, and electric vacuum pump relay 1 connector terminals No. 1 and No. 2 with jumper wires. Does the electric vacuum pump motor run? YES -Check for loose terminals in the electric vacuum pump relay 2 4P connector, the electric vacuum pump 2P connector, the brake pedal position switch 4P connector, and PCM connector A (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). NO -Go to step 24 .
24. Disconnect the electric vacuum pump 2P connector.
25. Measure voltage between body ground and electric vacuum pump 2P connector terminal No. 1. Is there battery voltage? YES -Go to step 26 . NO -Repair open in the wire between electric vacuum pump relay 2 and the electric vacuum pump.
26. Check for continuity between body ground and electric vacuum pump 2P connector terminal No. 2. Is there continuity? YES -Replace the electric vacuum pump (see «ELECTRIC VACUUM PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ). NO -Repair open in the wire between the electric vacuum pump and body ground (G503).

DTC P0571: Brake Pedal Position Switch Circuit

Note. DTC P0571 may be stored when both the brake pedal and the accelerator pedal are pressed at the same time for 5 minutes, and the vehicle speed is 12 mph (20 km/h) or more.

1. Turn the ignition switch to LOCK (0).
2. Check brake pedal position switch adjustment (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#conventional-brake-components) ). Is the switch adjustment OK ? YES -Go to step 3 . NO -Adjust the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#conventional-brake-components) ).
3. Turn the ignition switch ON (II).
4. Check the BRAKE PEDAL POSITION SWITCH in the DATA LIST with the HDS when the brake pedal is not pressed. Is OFF indicated? YES -Go to step 5 . NO -Go to step 9 .
5. Check the BRAKE PEDAL POSITION SWITCH in the DATA LIST with the HDS when the brake pedal is pressed. Is ON indicated? YES -Intermittent failure, the system is OK at this time. Check for loose terminals between the brake pedal position switch 4P connector and PCM connector A (44P). Refer to intermittent failures troubleshooting (see «INTERMITTENT FAILURES»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__intermittent-failures) ). NO -Go to step 6 .
6. Turn the ignition switch to LOCK (0).
7. Disconnect the brake pedal position switch 4P connector.
8. Check the brake pedal position switch (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exterior-lights/#exterior-lights) ). Is the switch OK? YES -Repair open in the wire between the brake pedal position switch and the PCM. NO -Replace the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#conventional-brake-components) ).
9. Turn the ignition switch to LOCK(0).
10. Disconnect the brake pedal position switch 4P connector.
11. Check the brake pedal position switch (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rdx/i-2006-2009/remont/exterior-lights/#exterior-lights) ). Is the switch OK? YES -Repair short in the wire between the brake pedal position switch and the PCM. NO -Replace the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#conventional-brake-components) ).

Note. This DTC is stored when there is a problem in the fuel and emission systems. Check for fuel and emission systems DTCs with the HDS, and go to the indicated DTCs troubleshooting (see GENERAL TROUBLESHOOTING INFORMATION ).

DTC P15B9: Check Valve (Intake Manifold) Leak Detected

1. Turn the ignition switch to LOCK (0).
2. Check for vacuum leaks at the check valve (intake manifold) between the brake booster and the intake manifold (see «BRAKE BOOSTER TEST»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#conventional-brake-components__brake-booster-test) ). Is the check valve OK? YES -Go to step 3 . NO -Replace the brake booster vacuum hose. (The check valve is inside the hose.)
3. Disconnect the vacuum hose from the brake booster.
4. Turn the ignition switch ON (II).
5. Check the BRAKE BOOSTER PRESSURE SENSOR, and BARO SENSOR in the DATA LIST with the HDS, then compare the two pressure values. Is the BRAKE BOOSTER PRESSURE SENSOR 8.67 kPa (2.56 in.Hg, 65 mmHg), more than the BARO SENSOR? YES -Replace the brake booster pressure sensor (see «BRAKE BOOSTER PRESSURE SENSOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ). NO -Intermittent failure, the system is OK at this time.

DTC P15BA: Check Valve (Intake Manifold) Stuck Closed

Special Tools Required

Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available

Note. If DTC P15BA is stored at the same time as DTC P0571, troubleshoot DTC P0571 first, then recheck for DTC P15BA.

Scheme 110

1. Turn the ignition switch to LOCK (0).
2. Disconnect the vacuum hose (A) from the brake booster pressure sensor (B), and connect a vacuum pump/gauge, 0-30 in.Hg, to the hose.
3. Turn the ignition switch ON (II).
4. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS before and after applying vacuum to the hose using the vacuum pump/gauge. Does the indicated value change? YES -Go to step 5 . NO -Replace the brake booster pressure sensor (see «BRAKE BOOSTER PRESSURE SENSOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ).
5. Turn the ignition switch OFF
6. Check for vacuum leaks or clogging at these parts: Brake booster pressure sensor hose. Brake booster vacuum hoses and their joints. Check valve (intake manifold). Check valve (vacuum pump) and filter. Brake booster. Are the parts OK? YES -Go to step 7 . NO -Repair or replace the leaking or clogged part(s).
7. Check the brake pedal position switch signal circuit (see «BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system) ). Is the circuit OK? YES -Intermittent failure, the system is OK at this time. Check for loose terminals between the brake pedal position switch 4P connector and PCM connector A (44P). Refer to intermittent failures troubleshooting (see «INTERMITTENT FAILURES»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__intermittent-failures) ). NO -Troubleshoot the brake pedal position switch signal circuit (see «DTC P0571: BRAKE PEDAL POSITION SWITCH CIRCUIT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__dtc-p0571-brake-pedal-position-switch) ).

DTC P15BB: Brake Booster System Leak Detected

Note. If DTC P15BB is stored at the same time as DTC P0571, troubleshoot DTC P0571 first, then recheck for DTC P15BB.

1. Turn the ignition switch to LOCK(0).
2. Check for vacuum leaks or clogging at these parts: Brake booster pressure sensor hose. Brake booster vacuum hoses and their joints. Check valve (intake manifold). Check valve (vacuum pump) and filter. Brake booster. Are the parts OK? YES -Go to step 3 . NO -Repair or replace the leaking or clogged part(s).
3. Check the brake pedal position switch signal circuit (see «BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING»(/acura/rdx/i-2006-2009/remont/engine-control-systems/#idle-control-system) ). Is the circuit OK? YES -Intermittent failure, the system is OK at this time. Check for loose terminals between the brake pedal position switch 4P connector and PCM connector A (44P). Refer to intermittent failures troubleshooting (see «INTERMITTENT FAILURES»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__intermittent-failures) ). NO -Troubleshoot the brake pedal position switch signal circuit (see «DTC P0571: BRAKE PEDAL POSITION SWITCH CIRCUIT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__dtc-p0571-brake-pedal-position-switch) ).

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1. Turn the ignition switch to LOCK(0).
2. Do the battery terminal disconnection procedure (see «DISCONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__disconnection) , and wait several seconds.
3. Do the battery terminal reconnection procedure (see «RECONNECTION»(/acura/rdx/i-2006-2009/remont/body-electrical/#battery__reconnection) , then do this procedure after the troubleshooting
4. Turn the ignition switch ON (II). Do not start the engine. Does the electric vacuum pump motor run? YES -Go to step 5 . NO -Go to step 21 .
5. Turn the ignition switch to LOCK (0).
6. Disconnect the vacuum hose (A) from the brake booster pressure sensor (B), and connect a vacuum pump/gauge, 0-30 in. Hg, to the hose.
7. Turn the ignition switch ON (II).
8. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS before and after applying vacuum to the hose using the vacuum pump/gauge. Does the indicated value change? YES -Go to step 9 . NO -Replace the brake booster pressure sensor (see «BRAKE BOOSTER PRESSURE SENSOR REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ).
9. Turn the ignition switch OFF.
10. Reconnect the vacuum hose to the brake booster.
11. Disconnect the brake booster vacuum hose from the intake manifold (see step 6 under «INTAKE MANIFOLD REMOVAL AND INSTALLATION»(/acura/rdx/i-2006-2009/remont/exhaust/#intake-manifold-and-exhaust-system) "Removal" ). NOTE: Cap the brake booster vacuum hose connector on the intake manifold to prevent a vacuum leak, or dust entering the system.
12. Deplete the booster vacuum by pressing the brake pedal several times until the brake pedal becomes hard.
13. Turn the ignition switch ON (II).
14. Check the ELECTRIC VACUUM PUMP RELAY in the DATA LIST with the HDS, and start the engine while pressing the brake pedal lightly. NOTE: Do not press the brake pedal hard; press the pedal gently until the brake lights turn on. Does the pump run and shut off within 8 seconds? YES -Intermittent failure, the system is OK at this time. Check for loose terminals between the brake booster pressure sensor 3P connector, the electric vacuum pump relay 2 4P connector, the electric vacuum pump 2P connector, and PCM connector B (44P). Refer to intermittent failures troubleshooting (see «HOW TO TROUBLESHOOT DTCS»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system__how-to-troubleshoot-dtcs) ). NO -Go to step 15 .
15. Turn the ignition switch to LOCK (0).
16. Substitute the known-good or new vacuum hose between the electric vacuum pump and 3-way joint.
17. Deplete booster vacuum by pressing the brake pedal several times until the brake pedal becomes hard.
18. Turn the ignition switch ON (II).
19. Check the ELECTRIC VACUUM PUMP RELAY in the DATA LIST with the HDS, and start the engine while pressing the brake pedal lightly. NOTE: Do not press the brake pedal hard; press the pedal gently until the brake lights turn on. Does the pump run and shut off within 8 seconds? YES -Replace the original vacuum hose between the electric vacuum pump and 3-way joint (see «COMPONENT LOCATION INDEX»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ). NO -Go to step 20 .
20. Check for vacuum leaks or clogging at these parts: Brake booster pressure sensor hose. Brake booster vacuum hoses and their joints. Check valve (intake manifold). Brake booster. Are the parts OK? YES -Replace the electric vacuum pump (see «ELECTRIC VACUUM PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ). NO -Repair or replace the leaking or clogged part(s).
21. Turn the ignition switch LOCK (0).
22. Check the connection and terminal fits of the electric vacuum pump 2P connector. Is the connector properly connected? YES -Go to step 23 . NO -Connect the electric vacuum pump 2P connector properly. If necessary, repair or replace the harness.
23. Remove electric vacuum pump relay 2, and check it (see «POWER RELAY TEST»(/acura/rdx/i-2006-2009/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES -Go to step 24 . NO -Replace electric vacuum pump relay 2.
24. Remove the No. 17 (15 A) fuse from the under-hood fuse/relay box.
25. Remove the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box.
26. Check for continuity between electric vacuum pump relay 2 terminal No. 2 and No. 31 (7.5 A) fuse in auxiliary under-hood fuse/relay box terminal No. 1. Is there continuity? YES -Go to step 27 . NO -Repair open in the wire between electric vacuum pump relay 2 and the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box.
27. Remove electric vacuum pump relay 1.
28. Install the No. 17 (15 A) fuse in the under-hood fuse/relay box.
29. Connect electric vacuum pump relay 2 connector terminals No. 1 and No. 2, and electric vacuum pump relay 1 connector terminals No. 1 and No. 2 with jumper wires. Does the electric vacuum pump motor run? YES -Check for loose terminals in the brake booster pressure sensor 3P connector, the electric vacuum pump relay 2 4P connector, the electric vacuum pump 2P connector, and PCM connector B (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). NO -Go to step 30 .
30. Disconnect the electric vacuum pump 2P connector.
31. Measure voltage between body ground and electric vacuum pump 2P connector terminal No. 1. Is there battery voltage? YES -Go to step 32 . NO -Repair open in the wire between electric vacuum pump relay 2 and the electric vacuum pump.
32. Check for continuity between body ground and electric vacuum pump 2P connector terminal No. 2. Is there continuity? YES -Replace the electric vacuum pump (see «ELECTRIC VACUUM PUMP REPLACEMENT»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ). NO -Repair open in the wire between the electric vacuum pump and body ground (G503).

Scheme 116

Scheme 117

Scheme 118

Scheme 119

1. Turn the ignition switch OFF.
2. Check the No. 17 (15 A) fuse in the under-hood fuse/relay box. Is the fuse blown? YES -Repair short in the wire between electric vacuum pump relay 1 and the No. 17 (15 A) fuse in the under-hood fuse/relay box. Replace the No. 17 (15 A) fuse, and recheck. NO -Reinstall the fuse, then go to step 3 .
3. Remove electric vacuum pump relay 1, and check it (see «POWER RELAY TEST»(/acura/rdx/i-2006-2009/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES -Go to step 4 . NO -Replace electric vacuum pump relay 1.
4. Measure voltage between body ground and electric vacuum pump relay 1 terminal No. 2. Is there battery voltage? YES -Go to step 5 . NO -Repair open in the wire between electric vacuum pump relay 1 and the No. 17 (15 A) fuse in the under-hood fuse/relay box.
5. Remove the No. 31 (7.5 A) fuse from the auxiliary under-hood fuse/relay box.
6. Check for continuity between electric vacuum pump relay 1 terminal No. 1 and the No. 31 (7.5 A) fuse in auxiliary under-hood fuse/relay box terminal No. 1. Is there continuity? YES -Go to step 7 . NO -Repair open in the wire between electric vacuum pump relay 1 and the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box.
7. Check for continuity between body ground and electric vacuum pump relay 1 terminal No. 3. Is there continuity? YES -Go to step 8 . NO -Repair open in the wire between electric vacuum pump relay 1 and body ground (G201).
8. Short the SCS line with the HDS.
9. Disconnect PCM connector A (44P).
10. Check for continuity between electric vacuum pump relay 1 terminal No. 4 and PCM connector A (44P) terminal No. 12. Is there continuity? YES -Check for loose terminals in the electric vacuum pump relay 1 4P connector, the electric vacuum pump 2P connector, and PCM connector A (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). NO -Repair open in the wire between electric vacuum pump relay 1 and the PCM.

Scheme 120

Scheme 121

1. Turn the ignition switch OFF.
2. Check the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box. Is the fuse blown? YES -Repair short in the wire between the electric vacuum pump relays 1 and 2 and the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box. Replace the No. 31 (7.5 A) fuse and recheck. NO -Remove the fuse, then go to step 3 .
3. Remove electric vacuum pump relay 1.
4. Check for continuity between electric vacuum pump relay 1 terminal No. 1 and the No. 31 (7.5 A) fuse in auxiliary under-hood fuse/relay box terminal No. 1. Is there continuity? YES -Go to step 5 . NO -Repair open in the wire between electric vacuum pump relay 1 and the No. 31 (7.5 A) fuse in auxiliary under-hood fuse/relay box.
5. Jump the SCS line with the HDS.
6. Disconnect PCM connector A (44P).
7. Check for continuity between the No. 31 (7.5 A) fuse in auxiliary under-hood fuse/relay box terminal No. 2 and PCM connector A (44P) terminal No. 13. Is there continuity? YES -Check for loose terminals in PCM connector A (44P), then update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). NO -Repair open in the wire between the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box and the PCM.

Scheme 122

Scheme 123

1. Turn the ignition switch OFF.
2. Remove electric vacuum pump relay 2, and check it (see «POWER RELAY TEST»(/acura/rdx/i-2006-2009/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES -Go to step 3 . NO -Replace electric vacuum pump relay 2.
3. Remove the No. 17 (15 A) fuse from the under-hood fuse/relay box.
4. Disconnect the electric vacuum pump 2P connector.
5. Check for continuity between electric vacuum pump relay 2 terminals No. 1 and No. 2. Is there continuity? YES -Repair short in the wires between electric vacuum pump relay 2 terminals No. 2 and No. 1. NO -Go to step 6 .
6. Jump the SCS line with the HDS.
7. Disconnect PCM connector A (44P).
8. Turn the ignition switch ON (II).
9. Measure voltage between body ground and PCM connector A (44P) terminal No. 12. Is there any voltage? YES -Repair short to power in the wire between electric vacuum pump relays 1 and 2 and the PCM. NO -Update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ).

Scheme 124

Scheme 125

Scheme 126

1. Turn the ignition switch OFF.
2. Remove electric vacuum pump relay 1, and check it (see «POWER RELAY TEST»(/acura/rdx/i-2006-2009/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES -Go to step 3 . NO -Replace electric vacuum pump relay 1.
3. Remove the No. 17 (15 A) fuse from the under-hood fuse/relay box and the No. 31 (7.5 A) fuse from the auxiliary under-hood fuse/relay box.
4. Check for continuity between electric vacuum pump relay 1 terminals No. 1 and No. 2. Is there continuity? YES -Repair short in the wires between electric vacuum pump relay 1 terminals No. 1 and No. 2. NO -Go to step 5 .
5. Jump the SCS line with the HDS.
6. Disconnect PCM connector A (44P).
7. Turn the ignition switch ON (II).
8. Measure voltage between body ground and PCM connector A (44P) terminal No. 13. Is there 3.0 V or more? YES -Repair short to power in the wire between the No. 31 (7.5 A) fuse in the auxiliary under-hood fuse/relay box and the PCM. NO -Go to step 9 .
9. Measure voltage between body ground and PCM connector A (44P) terminal No. 12. Is there any voltage? YES -Repair short to power in the wire between electric vacuum pump relays 1 and 2 and the PCM. NO -Update the PCM if it does not have the latest software, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rdx/i-2006-2009/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ).

Scheme 127

Scheme 128

Scheme 129

1. Remove the air cleaner housing cover (see «AIR CLEANER REMOVAL/INSTALLATION»(/acura/rdx/i-2006-2009/remont/mechanical/#intake-air-system) ).
2. Release the hooks (A), and move the under-hood fuse/relay box (B) aside. Do not disconnect the fuse/relay box connectors.
3. Remove the under-hood fuse/relay box stay (A).
4. Disconnect the brake booster pressure sensor connector (A).
5. Remove the brake booster pressure sensor (B), then disconnect the sensor hose (C). NOTE: Check for damage and deterioration of the sensor hose.
6. Install the brake booster pressure sensor in the reverse order of removal.
7. Install the under-hood fuse/relay box.
8. Start the engine, and check that the electric vacuum pump system indicator goes off (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/rdx/i-2006-2009/remont/mechanical-hydraulic/#electric-vacuum-pump-system) ).

Scheme 130

1. Disconnect the electric vacuum pump connector (A).
2. Disconnect the vacuum pump hose (B) from the electric vacuum pump (C).
3. Remove the pump from the bracket (D). NOTE: Do not disassemble the pump.
4. Inspect the pump bracket, and replace if necessary.
5. Install the electric vacuum pump in the reverse order of removal.
6. Start the engine, and check that the electric vacuum pump system indicator goes off.

See also:
• GENERAL TROUBLESHOOTING INFORMATION
• DLC CIRCUIT TROUBLESHOOTING
• SELF-DIAGNOSTIC FUNCTION
• PCM UPDATE
• SUBSTITUTING THE PCM
• PCM REPLACEMENT
• GENERAL TROUBLESHOOTING INFORMATION
• BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING
• DISCONNECTION
• RECONNECTION
• POWER RELAY TEST
• BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT
• HIGH MOUNT BRAKE LIGHT REPLACEMENT
• BRAKE BOOSTER TEST
• INTAKE MANIFOLD REMOVAL AND INSTALLATION
• AIR CLEANER REMOVAL/INSTALLATION
• DTC TROUBLESHOOTING
• P0556
• P0571
• P15B9
• P15BA
• P15BB
• INTERMITTENT FAILURES
• HOW TO TROUBLESHOOT DTCS