Toyota Tacoma (2015-2018) Service Manual: Lost Communication with ECM (C1437)
DESCRIPTION
The skid control ECU (master cylinder solenoid) receives signals from the ECM via the CAN communication system.
|
DTC Code |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
C1437 |
When the IG1 terminal voltage is 10 V or higher and the vehicle speed is 15 km/h (9 mph) or more, data cannot be sent from the ECM for 2 seconds or more. |
|
CAUTION / NOTICE / HINT
NOTICE:
When replacing the skid control ECU (master cylinder solenoid), perform calibration
(See page .gif)
).
PROCEDURE
|
1. |
CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION) |
(a) Using the Techstream, check for any momentary interruption in the wire harness
and connector corresponding to the DTC (See page
).
|
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
EFI Communication Open |
EFI communication open detection/ Error or Normal |
Normal |
- |
OK:
Normal (there are no momentary interruptions).
HINT:
Perform the above inspection before removing the sensor and connector.
| NG | .gif) |
GO TO STEP 3 |
|
.gif)
|
2. |
RECONFIRM DTC |
(a) Clear the DTCs (See page
).
(b) Turn the ignition switch off.
(c) Start the engine.
(d) Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.
(e) Check that no CAN communication system DTC is output (See page
).
(f) Check if the same DTC is output (See page
).
|
Result |
Proceed to |
|---|---|
|
DTC C1437 is not output |
A |
|
DTC C1437 is output |
B |
|
CAN communication system DTC is output |
C |
| A | |
USE SIMULATION METHOD TO CHECK |
| B | |
GO TO ENGINE CONTROL SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) |
| C | |
GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) |
|
3. |
REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - ECM) |
(a) Turn the ignition switch off.
(b) Repair or replace the harness or connector.
(c) Check for any momentary interruption between the skid control ECU (master
cylinder solenoid) and ECM (See page ).
(d) Check that there is no momentary interruption.
|
|
4. |
RECONFIRM DTC |
(a) Clear the DTCs (See page
).
(b) Turn the ignition switch off.
(c) Start the engine.
(d) Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.
(e) Check that no CAN communication system DTC is output (See page
).
(f) Check if the same DTC is output (See page
).
|
Result |
Proceed to |
|---|---|
|
DTC C1437 is not output |
A |
|
DTC C1437 is output |
B |
|
CAN communication system DTC is output |
C |
| A | |
END |
| B | |
REPLACE MASTER CYLINDER SOLENOID |
| C | |
GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) |
Yaw Rate Sensor Malfunction (C1436)
DESCRIPTION
The skid control ECU (master cylinder solenoid) receives signals from the yaw
rate and acceleration (airbag sensor assembly) via the CAN communication system.
The airbag sensor assembl ...
Steering Angle Sensor Initialization Incomplete (C1439,C1445)
DESCRIPTION
The skid control ECU (master cylinder solenoid) acquires steering angle sensor
(spiral cable with sensor sub-assembly) zero point every time the ignition switch
is turned to ON and th ...
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PROCEDURE
1.
VEHICLE BROUGHT TO WORKSHOP
NEXT
2.
CUSTOMER PROBLEM ANALYSIS
Click here
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Tire Pressure Monitor Receiver Communication Stop (B1247)
DESCRIPTION
The main body ECU (multiplex network body ECU) and tire pressure warning ECU
and receiver are connected using 2 direct lines that they use to communicate with
each other.
DTC No.
Detection Item
DTC Detection Condition
Trouble Area
...
Speed Sensor
Components
COMPONENTS
ILLUSTRATION
Removal
REMOVAL
PROCEDURE
1. REMOVE TRANSMISSION REVOLUTION SENSOR (NT)
(a) Disconnect the transmission revolution sensor (NT) connector.
(b) Remove the bolt and transmission revolution sensor (NT). ...
