Speed Signal Circuit [11/2021 - ]: Procedure

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Check the signal waveform according to the condition(s) in the table below.

   Item	Condition
   Tester connection	D21-25 (SI) - Body ground
   Tool setting	5 V/DIV., 20 ms./DIV.
   Condition	Ignition switch ON, wheel being rotated

   NOTE:

   Perform the inspection from the back of the connector with the connector connected.

   HINT: 

   When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

   Result

   Result	Proceed to
   The measured waveform is similar to that in the illustration	A
   The measured waveform is not similar to that in the illustration (Stuck low)	B
   The measured waveform is not similar to that in the illustration (Stuck high)	C

Result: 

B 

See step  6

Result: 

C 

See step  9

Result: 

A 

See step  2

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Check the signal waveform according to the condition(s) in the table below.

   Item	Condition
   Tester connection	D21-8 (+S) - Body ground
   Tool setting	5 V/DIV., 20 ms./DIV.
   Condition	Ignition switch ON, wheel being rotated

   NOTE:

   Perform the inspection from the back of the connector with the connector connected.

   HINT: 

   • When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.
   • The waveform (B) changes depending on the connected ECUs.

   Result

   Result	Proceed to
   The measured waveform is similar to that in the illustration	A
   The measured waveform is not similar to that in the illustration (Stuck low)	B
   The measured waveform is not similar to that in the illustration (Stuck high)	C

Result: 

B 

See step  4

Result: 

C 

REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

A 

See step  3

1. Disconnect the D1 radio and display receiver assembly connector.
2. Disconnect the D35 stereo component amplifier assembly connector.
3. Disconnect the D21 combination meter assembly connector.
4. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D1-8 (SPD) - D21-8 (+S)	Always	Below 1 Ω
   D35-17 (SPD) - D21-8 (+S)	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

CHECK THE VOLTAGE AT TERMINAL SPD OF EACH ECU 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Disconnect one of the connectors below.
   NOTE:

   After disconnecting a connector, perform all steps with all other devices connected.

   Connector	ECU
   D1	Radio and display receiver assembly
   D35	Stereo component amplifier assembly

2. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (Combination Meter Assembly)

   NOTE:

   • Make sure to perform this inspection with the wheels stopped.
   • Perform the inspection from the back of the connector with the connector connected.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   D21-8 (+S) - Body ground	Ignition switch ON	4.5 to 14 V

3. Repeat steps (a) and (b) for each connected ECU.

   HINT: 

   If the waveform changes to the waveform shown in the illustration after disconnecting a connector, an internal short in the disconnected ECU is suspected.

   Result

   Result	Proceed to
   After performing the inspection procedure for all connectors, the voltage did not change to the specified voltage	A
   When disconnecting the connector of the radio and display receiver assembly, the voltage changed to the specified voltage	B
   When disconnecting the connector of the stereo component amplifier assembly, the voltage changed to the specified voltage	C

Result: 

B 

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

C 

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

A 

See step  5

1. Disconnect the D1 radio and display receiver assembly connector.
2. Disconnect the D35 stereo component amplifier assembly connector.
3. Disconnect the D21 combination meter assembly connector.
4. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D1-8 (SPD) or D35-17 (SPD) - D21-8 (+S)	Always	Below 1 Ω
   D1-8 (SPD), D35-17 (SPD) or D21-8 (+S) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Check if smart access system with push-button start (for start function) DTCs are output.

   Body Electrical > Power Source Control > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are not output	A
   DTCs are output	B

Result: 

B 

GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (FOR START FUNCTION). Refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2021 - 03/2023]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2023 - ] 

Result: 

A 

See step  7

HINT: 

This procedure is performed to check the diode inside the combination meter assembly.

1. Remove the combination meter assembly.

   Refer to REMOVAL [11/2021 - ]

2. Measure the internal resistance of the combination meter assembly.

   Standard Resistance

   Tester Connection	Tester Connection	Condition	Measured Value
   D21-6 (IG+) - D21-25 (SI)	Positive (+) tester probe → D21-6 (IG+) Negative (-) tester probe → D21-25 (SI)	Always	A
   D21-6 (IG+) - D21-25 (SI)	Positive (+) tester probe → D21-25 (SI) Negative (-) tester probe → D21-6 (IG+)	Always	B

   OK

   There is a large difference between the measured value (A) and the measured value (B).

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

OK 

See step  8

1. Disconnect the D58 certification ECU (smart key ECU assembly) connector.
2. Disconnect the D21 combination meter assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D58-28 (SPDO) or D21-25 (SI) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [11/2021 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Check if smart access system with push-button start (for start function) DTCs are output.

   Body Electrical > Power Source Control > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are not output	A
   DTCs are output	B

Result: 

B 

GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (FOR START FUNCTION). Refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2021 - 03/2023]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2023 - ] 

Result: 

A 

See step  10

1. Disconnect the D58 certification ECU (smart key ECU assembly) connector.
2. Disconnect the D21 combination meter assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D58-28 (SPDO) - D21-25 (SI)	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [11/2021 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR