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Tire Pressure Warning System - Diagnostics: Other Lexus GX J120

Warning System 14 illustrations ~2355 words

TERMINALS OF ECU

HINT

Inspect the connectors from the back side while the connector is connected.

Scheme 92

Scheme 92: TERMINALS OF ECU
Scheme 92: TERMINALS OF ECU
Symbols (Terminals No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
IG (T15-2) - GND (T15-11)B-R - W-BIG power sourceIG switch ON10 to 14 V
SPD (T15-3) - GND (T15-11)V-R - W-BVehicle speed signalVehicle is runningPulse generation
SIL (T15-4) - GND (T15-11)W - W-BDiagnosis tester communication lineIG switch ON, when communication is not performed with a tester8 V or more
IND (T15-6) - GND (T15-11)L - W-BTire pressure warning lamp output signalIG switch ON, tire pressure warning lamp ON8 V or more
IND (T15-6) - GND (T15-11)L - W-BTire pressure warning lamp output signalIG switch ON, tire pressure warning lamp OFFBelow 1.5 V
RDA (T15-7) - GND (T15-11)G-B - W-BTire pressure monitor receiver input signalIG switch ON, when the tire pressure monitor receiver is not connected10 to 14 V
RF5V (T15-8) - GND (T15-11)G-R - W-BTire pressure monitor receiver power sourceIG switch ON4.5 to 5.5 V
IDSW (T15-9) - GND (T15-11)Y - W-BTire pressure warning switch input signalIG switch ON, tire pressure warning switch pushed inBelow 1.5 V
IDSW (T15-9) - GND (T15-11)Y - W-BTire pressure warning switch input signalIG switch ON, tire pressure warning switch released10 to 14 V
GND (T15-11) - Body groundW-B - Body groundGroundAlwaysBelow 1 ohms
TC (T15-12) - GND (T15-11)P-B - W-BTC terminalWhen terminal TC is not connected.8 V or more
GND2 (T15-16) - GND (T15-11)BR - W-BTire pressure monitor receiver groundAlwaysBelow 1 ohms

ECU CONNECTOR TERMINALS VOLTAGE SPECIFICATIONS

Scheme 93

Scheme 93: DIAGNOSIS SYSTEM
Scheme 93: DIAGNOSIS SYSTEM

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Scheme 99
  1. DIAGNOSIS SYSTEM Inspect the battery voltage. Battery voltage: 11 to 14 V If the voltage is below 11 V, recharge the battery before proceeding. Check DLC3. The vehicle's tire pressure monitor ECU uses ISO 9141-2 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format. Verify the conditions listed in «DLC3»(ref-228752-S37922094962006041100000) : DLC3 Terminal No. Disc. Connection / Voltage or Resistance Condition 7 SIL Bus + Line / Pulse generation During transmission 4 CG Chassis Ground to Body Ground /1 ohms or less Always 16 BAT Battery Positive to Body Ground /10 to 14 V Always HINT: If the hand-held tester display shows "UNABLE TO CONNECT TO VEHICLE" when the cable of the hand-held tester is connected to the DLC3, the ignition switch is turned to the ON position and the tester is operated, there is a problem on the vehicle side or tester side. If communication is normal when the tester is connected to another vehicle, inspect the DLC3 on the original vehicle. If communication is still not possible when the tool is connected to another vehicle, the problem is probably in the tester itself, so consult the Service Department listed in the tester's instruction manual. Warning lamp The tire pressure warning lamp blinks when there is any malfunction in the tire pressure warning system. NOTE: When the malfunction has been corrected, the tire pressure warning lamp does not come on. DTCs (Normal mode) DTCs are memorized in the tire pressure monitor ECU and read by the blinks of the tire pressure warning lamp or using the hand-held tester (see «DTC CHECK/CLEAR»(ref-228752-S38931515762006041100000) for the procedure of DTCs check). Test mode By switching from normal mode into test mode, you can inspect the tire pressure monitor receiver assy, each tire pressure monitor valve sub-assy, vehicle speed sensor, tire pressure monitor ECU and tire pressure warning switch (see «TEST MODE PROCEDURE»(ref-228752-S19174676342006041100000) ).
  2. CHECK WARNING LAMP Turn the ignition switch to the ON position. Check that the tire pressure warning lamp comes on for 3 seconds. If the warning check result is not normal, proceed to the troubleshooting for the tire pressure warning lamp circuit. WARNING LAMP Trouble Area Reference Tire pressure warning lamp circuit «TIRE PRESSURE WARNING LAMP CIRCUIT»(ref-228752-S11713001452006041100000)
  3. TIRE PRESSURE WARNING LAMP TABLE *1: Comes on and goes off repeatedly at 0.5 second intervals. *2: Comes on and goes off repeatedly at 0.25 second intervals. *3: Comes on and goes off repeatedly at 0.125 second intervals.

Scheme 100

Scheme 100: DTC CHECK/CLEAR
Scheme 100: DTC CHECK/CLEAR

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Scheme 104
  1. DTC CHECK (USING SST CHECK WIRE) Check DTCs. Using the SST, connect terminals TC and CG of the DLC3. SST 09843-18040 Turn the ignition switch to the ON position. Read and record any DTCs from the tire pressure warning lamp on the combination meter. (Scheme 102)for examples of a normal system code and codes 13 and 33. HINT: If the tire pressure warning lamp does not output any DTCs or the normal system code, inspect the tire pressure warning lamp circuit or TC terminal circuit. TROUBLE AREA REFERENCE TABLE Trouble Area Reference Tire pressure warning lamp circuit «TIRE PRESSURE WARNING LAMP CIRCUIT»(ref-228752-S11713001452006041100000) TC terminal circuit «TC TERMINAL CIRCUIT»(ref-228752-S22395551272006041100000) If 2 or more malfunctions are indicated at the same time, the lowest numbered DTC is displayed first. Refer to the «DIAGNOSTIC TROUBLE CODE TABLE»(ref-228752-S25618356882006041100000) for DTC information. After completing the check, turn the ignition switch off and remove the SST from the DLC3. SST 09843-18040 Clear the DTCs. Using the SST, connect terminals TC and CG of the DLC3. SST 09843-18040 Turn the ignition switch to the ON position. Within 15 seconds after connecting terminals TC and CG, change the tire pressure warning switch between "MAIN" and "2nd" 4 cycles or more. Check that the blinking pattern of the tire pressure warning lamp shows the normal system code. Disconnect the SST from the terminals of the DLC3.
  2. DTC CHECK (USING HAND-HELD TESTER) Check DTCs. Connect the hand-held tester to the DLC3. Turn the ignition switch to the ON position. Read the DTCs following the prompts on the tester screen. HINT: Refer to the hand-held tester operator's manual for further details. Clear the DTCs. HINT: After repairing the malfunctions, clear the DTC. Connect the hand-held tester to the DLC3. Turn the ignition switch to the ON position. Erase the DTCs following the prompts on the tester screen. HINT: Refer to the hand-held tester operator's manual for further details.

Scheme 105

Scheme 105: DATA LIST/ACTIVE TEST
Scheme 105: DATA LIST/ACTIVE TEST
  1. DATA LIST Connect the hand-held tester to the DLC3. Turn the ignition switch to the ON position. Following the display on the hand-held tester, read the "DATA LIST".

IDENTIFY TRANSMITTER (ERROR IN PRESENT)

HINT

  1. Refer to this part of the article if a DTC is currently output. If a DTC in the range C2165/65 to C2169/69 is output previously and currently or any other DTC was output previously but not currently, refer to «IDENTIFY TRANSMITTER (ERROR IN PAST)»(ref-228752-S11887294042006041100000) .
  2. DTCs relevant to the transmitters are corresponding to each transmitter ID. It is impossible to identify which tire is malfunctioning according to each transmitter ID. Therefore the following procedure must be done to confirm the ID No. and tire location.

IDENTIFY PROCEDURE

  1. Set the pressure of all tires to the specified value. TIRES PRESSURE SPECIFICATIONS Front Rear Spare 220 kPa (2.2 kgf/cm 2 , 32 psi) 220 kPa (2.2 kgf/cm 2 , 32 psi) 220 kPa (2.2 kgf/cm 2 , 32 psi) Go to next step.
  2. Rapidly reduce the pressure of front right wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  3. Using hand-held tester, check the tire pressure data of each wheel. Do any of TIREPRESS1 through 5 indicate 120 kPa (1.2 kgf/cm 2 , 17 psi)? TIRE PRESSURE DATA (FRONT RIGHT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 min. ID1 tire pressure/: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS2 min. ID2 tire pressure/: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS3 min. ID3 tire pressure/: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS4 min. ID4 tire pressure/: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS5 min. ID5 tire pressure/: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure NO: The detected DTC is for the front right wheel transmitter. YES: Go to next step.
  4. Rapidly reduce the pressure of front left wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  5. Using hand-held tester, check the tire pressure data of each wheel. Do any of TIREPRESS1 through 5 indicate 120 kPa (1.2 kgf/cm 2 , 17 psi)? TIRE PRESSURE DATA (FRONT LEFT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS2 ID2 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS3 ID3 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS4 ID4 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS5 ID5 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure NO: The detected DTC is for the front left wheel transmitter. YES: Go to next step.
  6. Rapidly reduce the pressure of rear right wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  7. Using hand-held tester, check the tire pressure data of each wheel. Do any of TIREPRESS1 through 5 indicate 120 kPa (1.2 kgf/cm 2 , 17 psi)? TIRE PRESSURE DATA (REAR RIGHT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS2 ID2 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS3 ID3 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS4 ID4 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS5 ID5 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure NO: The detected DTC is for the rear right wheel transmitter. YES: Go to next step.
  8. Rapidly reduce the pressure of rear left wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  9. Using hand-held tester, check the tire pressure data of each wheel. Do any of TIREPRESS1 through 5 indicate 120 kPa (1.2 kgf/cm 2 , 17 psi)? TIRE PRESSURE DATA (REAR LEFT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS2 ID2 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS3 ID3 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS4 ID4 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure TIREPRESS5 ID5 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure NO: The detected DTC is for the rear left wheel transmitter. YES: The detected DTC is for the spare tire transmitter.

IDENTIFY TRANSMITTER (ERROR IN PAST)

HINT

  1. Refer to "IDENTIFY TRANSMITTER (ERROR IN PRESENT)" if a DTC is currently output. If a DTC in the range C2165/65 to C2169/69 is output previously and currently or any other DTC was output previously but not currently, refer to «IDENTIFY TRANSMITTER (ERROR IN PAST)»(ref-228752-S11887294042006041100000) .
  2. DTCs relevant to the transmitters are corresponding to each transmitter ID. It is impossible to identify which tire is malfunctioning according to each transmitter ID. Therefore the following procedure must be done to confirm the ID No. and tire location.
  3. The following procedure is used to identify which wheel's transmitter the ID1 is resulting from when C2141/41 (Transmitter ID1 error) or C2165/65 (Abnormal temperature inside ID1 tire) is detected. Identify the corresponding transmitter using the same procedure when DTCs C2142/42 to C2145/45, C2166/66 to C2169/69 are detected.
  1. Set the pressure of all tires to the specified value. TIRES PRESSURE SPECIFICATIONS Front Rear Spare 220 kPa (2.2 kgf/cm 2 , 32 psi) 220 kPa (2.2 kgf/cm 2 , 32 psi) 220 kPa (2.2 kgf/cm 2 , 32 psi) Go to next step.
  2. Rapidly reduce the pressure of front right wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  3. Using hand-held tester, check the ID1 tire pressure data. ID1 TIRE PRESSURE DATA (FRONT RIGHT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure Go to next step.
  4. Is ID1 tire pressure 120 kPa (1.2 kgf/cm 2 , 17 psi)? YES: The ID1 is for the front right wheel transmitter. NO: Go to next step.
  5. Rapidly reduce the pressure of front left wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  6. Using hand-held tester, check the ID1 tire pressure data. ID1 TIRE PRESSURE DATA (FRONT LEFT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure Go to next step.
  7. Is ID1 tire pressure 120 kPa (1.2 kgf/cm 2 , 17 psi)? YES: The ID1 is for the front left wheel transmitter. NO: Go to next step.
  8. Rapidly reduce the pressure of rear right wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  9. Using hand-held tester, check the ID1 tire pressure data. ID1 TIRE PRESSURE DATA (REAR RIGHT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure Go to next step.
  10. Is ID1 tire pressure 120 kPa (1.2 kgf/cm 2 , 17 psi)? YES: The ID1 is for the rear right wheel transmitter. NO: Go to next step.
  11. Rapidly reduce the pressure of rear left wheel to 120 kPa (1.2 kgf/cm 2 , 17 psi). Go to next step.
  12. Using hand-held tester, check the ID1 tire pressure data. ID1 TIRE PRESSURE DATA (REAR LEFT WHEEL) Item Measurement item / Range (Display) Normal Condition TIREPRESS1 ID1 tire pressure/ min.: 0 kPa (0 kgf.cm 2 , 0 psi), max.: 637.5 kPa (6.48 kgf.cm 2 , 92.2 psi) Actual tire pressure Go to next step.
  13. Is ID1 tire pressure 120 kPa (1.2 kgf/cm 2 , 17 psi)? YES: The ID1 is for the rear left wheel transmitter. NO: The ID1 is for the spare tire transmitter.

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