Toyota RAV4 (XA40) 2013-2018 Service Manual: Communication malfunction no. 1
Description
This dtc is output when a communication error occurs between the transponder key amplifier and transponder key ecu. Some possible reasons for the communication error are: 1) 2 or more ignition keys are positioned too close together, or 2) noise is occurring in the communication line.
Wiring diagram
Inspection procedure
- Check key
- Check if the ignition key being used is near other ignition keys. Also, check if the key ring is in contact with the key grip.
Result:
- Check for dtc
- Separate the keys from each other and / or remove the key ring.
- Clear the dtc (see page ei-18).
- Insert a key into the ignition key cylinder. Remove it.
Repeat for all other keys.
- Check that no dtc is output.
Ok: no dtc is output.
- Check transponder key ecu (noise)
- Using an oscilloscope or the intelligent tester, check for noise in the waveform between the terminals of the e5 amplifier connector and e46 ecu connector.
Ok:
no noise is present (see illustration).
- Check wire harness (transponder key ecu - transponder key amplifier)
- Disconnect the e46 ecu connector.
- Disconnect the e5 amplifier connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance 
- Check transponder key amplifier (operation)
- Temporarily replacing the transponder key amplifier with a new or normally functioning one.
- Check that the engine starts normally.
Ok: engine starts.
End (transponder key amplifier is defective)
Communication
Description
When a key is inserted into the ignition key cylinder but no communication
occurs between the key and
transponder key ecu, dtc b2796 is output. When a key is inserted into the
ig ...
Engine immobiliser system malfunction
Description
This dtc is output when one of the following occurs: 1) the ecm detects
errors in its own
communications with the transponder key ecu; 2) the ecm detects errors in the
communicat ...
Other materials:
Diagnosis system
Description
The occupant classification ecu controls the functions of
the occupant classification system on the vehicle. Data
of the occupant classification system can be read in the
data link connector 3 (dlc3) of the vehicle. When the
system seems to be malfunctioning, use the intelligen ...
Trailer towing
Your vehicle is designed
primarily as a passenger-and-
load-carrying vehicle.
Towing a trailer can have an
adverse impact on handling,
performance, braking, durability,
and fuel consumption.
For your safety and the
safety of others, you must
not overload your vehicle or
trailer. You must also
ensu ...
Engine (ignition) switch
(vehicles with a
smart key system)
Performing the following operations when carrying the electronic
key on your person starts the engine or changes engine
switch modes.
Starting the engine
Check that the parking brake is set.
Check that the shift lever is set in p.
Firmly depress the brake pedal.
The smart key system in ...
