DTC No.
   Indicates the diagnostic trouble code.
 Page or Instructions
   Indicates the page where the inspection procedure
   for each circuit is to be found, or gives instructions
   for checking and repairs.
 Detection Item
   Indicates the system of the problem or
   contents of the problem. Trouble Area
   Indicates the suspect area of the 
   problem.
Mass Air Flow Circuit MalfunctionDetection Item
 Open or short in mass air flow meter circuit
 Mass air flow meter
 ECM DTC No.
(See page)Trouble AreaMIL* MemoryP0100
(DI-24)
P0101
(DI-28)
P0115
(DI-33) Open or short in intake air temp. sensor 
   circuit
 Intake air temp. sensor
 ECM Intake Air Temp. Circuit 
Malfunction P0110
(DI-29)
 Open or short in engine coolant temp. sensor circuit
 Engine coolant temp. sensor
 ECM
Throttle/ Pedal Position Sensor/Switch
ºAº Circuit MalfunctionEngine Coolant Temp. 
Circuit Malfunction
 Open or short in throttle position sensor circuit
 Throttle position sensor
 ECM
DTC CHART (SAE Controlled)
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument or other
factors.
If a malfunction code is displayed during the DTC check mode, check the circuit for that code listed in the table
below. For details of each code, turn to the page referred to under the ºSee pageº for the respective ºDTC No.º
in the DTC chart.
Mass Air Flow Circuit
Range/ Performance Problem Mass air flow meter
 Throttle position sensor Throttle/ Pedal Position Sensor/ Switch
ºAº Circuit Range / Performance Prob-
lem P0116
(DI-37)Engine Coolant Temp. 
Circuit Range/ Performance Problem Engine coolant temp. sensor
 Cooling system
IN-26- INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED 
SYSTEMS
26 Author: Date:
2001 AVALON   (RM808U)
4. DIAGNOSTIC TROUBLE CODE CHART
The inspection procedure is shown in the table below. This table permits efficient and accurate troubleshoot-
ing using the diagnostic trouble codes displayed in the diagnostic trouble code check. Proceed with trouble-
shooting  in accordance with the inspection procedure given in the diagnostic chart corresponding to the
diagnostic  trouble codes displayed. The engine diagnostic trouble code chart is shown below as an example.