DTC C2191/91: Vehicle Speed Signal Error (Test Mode DTC): Procedure

1. Turn the ignition switch off.
2. Connect Techstream to the DLC3.
3. Turn the ignition switch on (IG) and turn the tester on.
4. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
5. Check that the values indicated on the tester and on the combination meter are the same.
   TIRE PRESSURE MONITOR
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Vehicle Speed	Vehicle speed/ min.: 0 km/h (0 mph) max.: 255 km/h (158 mph)	Almost same as actual vehicle speed	Speed indicated on combination meter

   OK

   Vehicle speed indicated on the tester and on the combination meter are the same.

NG → See step   2 

OK → See step   4 

1. Disconnect the D33 ECU connector.
   Fig 1: Checking Harness And Connector (ECU - Combination Meter)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the E1 meter connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   D33-2 (SPD) - E1-9 (+S)	Always	Below 1 Ω
   D33-2 (SPD) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Remove the combination meter. Refer to REMOVAL .
   Fig 2: Checking Tire Pressure Warning ECU (SPD Signal)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Reconnect D33 and E1 connectors.
3. Jack up the vehicle.
4. Shift the lever to the neutral position.
5. Turn the ignition switch on (IG).
6. Check the waveform of the ECU connector using an oscilloscope while turning the wheel slowly.

   Result

   Tester Connection	Switch Condition	Specified Condition
   E1-9 (+S) - Body ground	Ignition switch on (IG)	Correct waveform appears as shown

   TOOL SETTING
   
   

   Item	Contents
   Tool Setting	5 V/DIV., 20 ms/DIV.
   Vehicle Condition	Driving wheel rotating slowly

   OK

   The waveform is displayed as shown in the illustration.

   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.

NG → See step   6 

OK → See step   5