DTC B15C2: Speed Signal Malfunction: Procedure

1. Drive the vehicle and check if the function of the speedometer in the No. 1 meter ECU sub-assembly is normal.

   OK

   Actual vehicle speed and the speed indicated on the speedometer are the same.

   HINT: 

   The vehicle speed sensor is functioning normally when the indication on the speedometer is normal.

NG → See step   6 

OK: Go to next step 

1. Enter the "GPS & Vehicle Sensor" (Vehicle Sensors). Refer toOPERATION CHECK .
   Fig 1: Screen Display - GPS & Vehicle Sensor

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. While driving the vehicle, compare the "SPD" indicator to the reading on the speedometer. Check if these readings are equal or almost equal.

   OK

   The readings are equal or almost equal.

NG → See step   4 

OK: Go to next step 

1. Disconnect the L59 display and navigation module display connector.
2. Disconnect the L10 No. 1 meter ECU sub-assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   L59-18 (SPD) - L10-10 (+S)	Always	Below 1 Ω
   L59-18 (SPD) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Remove the No. 1 meter ECU sub-assembly with the connector(s) still connected.
   Fig 2: Check No. 1 Meter ECU Sub-Assembly (Speed Signal) & Waveform

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect an oscilloscope to terminal L10-10 (+S) and body ground.
3. Turn the engine switch on (IG).
4. Check the signal waveform according to the condition(s) in the table below.
   MEASUREMENT CONDITION
   
   

   Item	Condition
   Terminal No. (Symbol)	L10-10 (+S) - Body ground
   Tool setting	5 V/DIV., 20 ms./DIV.
   Condition	Vehicle being driven at approx, 20 km/h (12 mph)

   OK

   The waveform display is as shown in the illustrationFig 2.

   HINT: 

   When the system is function normally, one wheel revolution generates 4 pulses.

   As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (No. 1 Meter ECU Sub-assembly)

NG → See step   7 

OK → See step   5