DESCRIPTION
The electronic throttle control system has a dedicated power supply circuit. The voltage (+BM) is monitored and when it is low (below 4 V), the ECM determines that there is a malfunction in the electronic throttle control system and cuts off the current to the throttle actuator.
When the voltage becomes unstable, the electronic throttle control system itself becomes unstable. For this reason, when the voltage is low, the current to the throttle actuator is cut. If repairs are made and the system returns to normal, turn the ignition switch off. The ECM then allows the current to flow to the throttle actuator so that it can be restarted.
HINT:
The electronic throttle control system does not use a throttle cable.
DTC No. |
DTC Detection Condition |
Trouble Area |
---|---|---|
P2118 |
An open in the electronic throttle control system power source (+BM) circuit (1 trip detection logic). |
|
MONITOR DESCRIPTION
The ECM monitors the battery supply voltage applied to the throttle actuator.
When the power supply voltage (+BM) drops below 4 V for 0.8 seconds or more, the ECM interprets this as an open in the power supply circuit (+BM). The ECM illuminates the MIL and stores the DTC.
If the malfunction is not repaired successfully, the DTC is stored 5 seconds after the engine is next started.
MONITOR STRATEGY
Related DTCs |
P2118: Electronic Throttle Actuator Power Supply Line Range Check (Low Voltage) |
Required Sensors/Components (Main) |
Throttle actuator, throttle valve (throttle body) ETCS fuse |
Required Sensors/Components (Related) |
None |
Frequency of Operation |
Continuous |
Duration |
0.8 seconds |
MIL Operation |
Immediate |
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
Monitor runs whenever following DTCs not stored |
None |
Both of the following conditions are met |
- |
Battery voltage |
8 V or higher |
Command to electronic throttle actuator power |
ON |
TYPICAL MALFUNCTION THRESHOLDS
Electronic throttle actuator power supply voltage |
Below 4 V |
COMPONENT OPERATING RANGE
Electronic throttle control |
Normal |
CONFIRMATION DRIVING PATTERN
HINT:
Techstream Display |
Description |
---|---|
NORMAL |
|
ABNORMAL |
|
INCOMPLETE |
|
N/A |
|
HINT:
HINT:
FAIL-SAFE
When this DTC or other DTCs relating to Electronic Throttle Control System (ETCS) malfunctions, are stored, the ECM enters fail-safe mode. During fail-safe mode, the ECM cuts the current to the throttle actuator, and the throttle valve is returned to a 6° throttle angle by the return spring. The ECM then adjusts the engine output by controlling the fuel injection (intermittent fuel-cut) and ignition timing, in accordance with the accelerator pedal opening angle, to allow the vehicle to continue at a minimal speed. If the accelerator pedal is depressed firmly and gently, the vehicle can be driven slowly.
Fail-safe mode continues until a pass condition is detected, and the ignition switch is then turned off.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. |
READ VALUE USING TECHSTREAM (+BM VOLTAGE) |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Data List / +BM Voltage.
(e) Read the value displayed on the Techstream.
Standard voltage:
11 to 14 V
OK |
CHECK FOR INTERMITTENT PROBLEMS |
|
2. |
CHECK HARNESS AND CONNECTOR (BATTERY - ECM, ECM - BODY GROUND) |
(a) Disconnect the ECM connectors.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
A49-3 (+BM) - Body ground |
Always |
11 to 14 V |
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Tester Connection |
Condition |
Specified Condition |
---|---|---|
B58-19 (ME01) - Body ground |
Always |
Below 1 Ω |
B58-104 (E1) - Body ground |
Always |
Below 1 Ω |
OK |
REPLACE ECM |
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
Terminals Of Ecu
TERMINALS OF ECU
1. CHECK MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY)
(a) Disconnect the 2A, 2C and 2F main body ECU (driver side junction block assembly)
connectors.
(b) Measure the voltage and resistance according to the value(s) in the table ...
Back-up Power Source Circuit
DESCRIPTION
The back-up power source circuit for the A/C amplifier is shown below. Power
is supplied even when the ignition switch is turned off. The power is used for diagnostic
trouble code memory, etc.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE ...
Disassembly
DISASSEMBLY
PROCEDURE
1. REMOVE STEERING RACK BOOT CLIP (for LH Side)
(a) Using pliers, remove the steering rack boot clip.
2. REMOVE STEERING RACK BOOT CLIP (for RH Side)
HINT:
Perform the same procedure as for the LH side.
3. REMOVE NO. 2 STEERING RAC ...