DESCRIPTION
The navigation ECU receives a vehicle speed signal from the combination meter assembly.
HINT:
WIRING DIAGRAM
PROCEDURE
| 1. |
CHECK COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM) |
| (a) Check the output waveform. (1) Remove the combination meter assembly with the connector(s) still connected. (2) Connect an oscilloscope to terminal K21-6 (+S) and body ground. (3) Turn the engine switch on (IG). (4) Turn a wheel slowly. (5) Check the signal waveform according to the condition(s) in the table below.
OK: The waveform is similar to that 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 | | GO TO METER / GAUGE SYSTEM
|
|
| 2. |
CHECK HARNESS AND CONNECTOR (NAVIGATION ECU - COMBINATION METER ASSEMBLY) |
(a) Disconnect the K17 navigation ECU connector.
(b) Disconnect the K21 combination meter assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection | Condition |
Specified Condition |
|---|---|---|
|
K17-9 (SPD) - K21-6 (+S) |
Always | Below 1 Ω |
| OK | | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE
|
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter
Reverse Signal Circuit
Reverse Signal Circuit between Radio Receiver Assembly and Navigation ECU
Parts Location
Wireless charger (if equipped)