Toyota RAV4 (XA40) 2013-2018 Service Manual: Ecm power source circuit
Description
When the ignition switch is turned on, the battery voltage is applied to the
igsw of the ecm. The output
signal from the mrel terminal of the ecm causes a current to flow to the coil,
closing the contacts of the
integration relay (efi main relay) and supplying power to either terminal +b or
+b2 of the ecm.
Wiring diagram
Inspection procedure
- Inspect fuses (p/i, am2, ig2, efi main, ign)
- Remove the p/i fuse, am2 fuse, ig2 fuse and efi main
fuse from the engine room no. 1 Relay block.
- Remove the ign fuse from the instrument panel junction
block.
- Measure the resistance of the fuses.
Standard resistance:
below 1
- Reinstall the fuses.
- Inspect relay (ig2, efi main)
- Remove the integration relay and ig2 relay from the
engine room no. 1 Relay block.
- Measure the resistance between the terminal of the
integration relay.
Standard resistance
- Measure the resistance between the terminal of the ig2
relay.
Standard resistance
- Reinstall the relay.
- Check harness and connector (ecm - body ground)
- Disconnect the b30 ecm connector.
- Measure the resistance.
Standard resistance
- Reconnect the ecm connector.
- Inspect ecm (igsw voltage)
- Disconnect the b30 and a9 ecm connectors.
- Turn the ignition switch on.
- Measure the voltage between the terminals of the b30
and a9 ecm connectors.
Standard voltage
- Reconnect the ecm connector.
- Check harness and connector (relay block - ecm, ignition switch,
battery)
- Disconnect the a9 ecm connector.
- Disconnect the e3 ignition switch connector.
- Disconnect the battery positive terminal.
- Remove the am2 fuse and ig2 relay.
- Measure the resistance between the terminals.
Standard resistance (check for open)
Standard resistance (check for short)
- Reinstall the relay and fuse.
- Reconnect the connectors.
- Inspect ignition switch (see page es-261)
- Check harness and connector (integration relay - ecm, battery, body
ground)
- Disconnect the a9 ecm connector.
- Remove the integration relay from the engine room no. 1
Relay block.
- Disconnect the integration relay connector.
- Remove the p/i fuse from the engine room no. 1 Relay
block.
- Check the resistance between the terminals.
Standard resistance (check for open)
Standard resistance (check for short)
- Reconnect the connectors.
- Reinstall the integration relay and p/i fuse.
Related dtcs
If any evap system dtcs are set, the malfunctioning area can be determined
using the table below.
Notice:
If the reference pressure difference between the first and second ch ...
Description
The ecm constantly generates 5 v power from the battery voltages supplied to
the +b (batt) terminal to
operate the microprocessor. The ecm also provides this power to the sensors
thr ...
Other materials:
Installation
Hint:
Use the same procedures for the lh side and rh side.
The procedures listed below are for the lh side.
Install speed sensor front lh
Notice:
To prevent interference with other parts, do not twist
the sensor wire's painted line areas when installing
it.
Set the sensor body ...
Terminals of ecu
Check instrument panel junction block (main body ecu)
Disconnect the ib and ie junction block connectors.
Measure the voltage and resistance of the wire
harness side connectors.
Reconnect the ib and ie junction block connector.
Measure the voltage of the wire harness ...
How to proceed with troubleshooting
Hint:
Use the following procedures to troubleshoot the occupant
classification system.
*: Use the intelligent tester.
Vehicle brought to workshop
Passenger airbag on/off indicator check
Dtc check (present and past dtc)*
Check for dtcs (see page rs-249 ).
Result ...