Toyota RAV4 manuals

Toyota Sienna Service Manual: Oxygen (A/F) Sensor Heater Control Circuit Low/ Oxygen (A/F) Sensor Heater Control Circuit High

Toyota Sienna Service Manual / 2GR-FE Engine control system / SFI system / Diagnostic trouble code chart / Oxygen (A/F) Sensor Heater Control Circuit Low/ Oxygen (A/F) Sensor Heater Control Circuit High

DTC P0031 Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 1 Sensor 1)

DTC P0032 Oxygen (A/F) Sensor Heater Control Circuit High (Bank 1 Sensor 1)

DTC P0051 Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 2 Sensor 1)

DTC P0052 Oxygen (A/F) Sensor Heater Control Circuit High (Bank 2 Sensor 1)

HINT:

DESCRIPTION

Refer to DTC P2195.

HINT:

DESCRIPTION

DTC No.

DTC Detection Condition

Trouble Area

P0031
P0051

Air-Fuel Ratio (A/F) sensor heater current less than 0.8 A (1 trip detection logic)
  • Open in A/F sensor heater circuit
  •  A/F sensor heater
  •  A/F sensor heater relay
  •  ECM

P0032
P0052

Air-Fuel Ratio (A/F) sensor heater current more than 10 A (1 trip detection logic)
  • Short in A/F sensor heater circuit
  •  A/F sensor heater
  •  A/F sensor heater relay
  •  ECM

HINT:

MONITOR DESCRIPTION

The ECM uses information from the Air-Fuel Ratio (A/F) sensor to regulate the air-fuel ratio and keep it close to the stoichiometric level. This maximizes the ability of the Three-Way Catalytic Converter (TWC) to purify the exhaust gas.

The A/F sensor detects oxygen levels in the exhaust gas and transmits the information to the ECM. The inner surface of the sensor element is exposed to the outside air. The outer surface of the sensor element is exposed to the exhaust gas. The sensor element is made of platinum coated zirconia and includes an integrated heating element.

The zirconia element generates small voltage when there is a large difference in the oxygen concentrations between the exhaust gas and outside air. The platinum coating amplifies this voltage generation.

The A/F sensor is more efficient when heated. When the exhaust gas temperature is low, the sensor cannot generate useful voltage signals without supplementary heating. The ECM regulates the supplementary heating using a duty-cycle approach to adjust the average current in the sensor heater element. If the heater current is outside the normal range, the signal transmitted by the A/F sensor will be inaccurate, as a result, the ECM will be unable to regulate air-fuel ratio properly.

When the current in the A/F sensor heater is outside the normal operating range, the ECM interprets this as a malfunction in the sensor heater and sets a DTC.

Example: The ECM sets DTC P0032 or P0052 when the current in the A/F sensor heater is more than 10 A.

Conversely, when the heater current is less than 0.8 A, DTC P0031 or P0051 is set.

MONITOR STRATEGY

MONITOR DESCRIPTION

TYPICAL ENABLING CONDITIONS

All:

TYPICAL ENABLING CONDITIONS

P0031 and P0051:

TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

P0032 and P0052:

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

P0031 and P0051:

TYPICAL MALFUNCTION THRESHOLDS

P0032 and P0052:

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

MONITOR RESULT

Refer to CHECKING MONITOR STATUS.

WIRING DIAGRAM

Refer to DTC P2195.

INSPECTION PROCEDURE

HINT: Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

1 INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)

INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)

  1. Disconnect the A5 or A6 A/F sensor connector.
  2.  Measure the resistance according to the value(s) in the table below.

Standard resistance: Bank 1

Standard resistance

Bank 2

Standard resistance

  1. Reconnect the A/F sensor connector.

Result

Result

2 CHECK TERMINAL VOLTAGE (+B OF A/F SENSOR)

CHECK TERMINAL VOLTAGE

  1. Disconnect the A5 or A6 A/F sensor connector.
  2.  Turn the ignition switch to the ON position.
  3.  Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

  1. Reconnect the A/F sensor connector

3 INSPECT FUSE (A/F FUSE)

INSPECT FUSE (A/F FUSE)

  1. Remove the A/F fuse from the engine room junction block.
  2.  Measure the resistance according to the value(s) in the table below.

    Standard resistance: Below 1 Ω

  3.  Reinstall the A/F fuse

4 INSPECT RELAY (A/F RELAY)

INSPECT RELAY (A/F RELAY)

  1. Remove the A/F relay from the No. 6 engine room relay block.
  2.  Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

  1. Reinstall the A/F relay.

5 CHECK HARNESS AND CONNECTOR (A/F SENSOR - A/F RELAY)

CHECK HARNESS AND CONNECTOR (A/F SENSOR - A/F RELAY)

  1. Disconnect the A5 or A6 A/F sensor connector.
  2.  Remove the A/F relay from the No. 6 engine room relay block.
  3.  Measure the resistance according to the value(s) in the table below.

Standard resistance: Check for open

Standard resistance

Check for short

Standard resistance

  1. Reinstall the A/F relay.
  2.  Reconnect the A/F sensor connector

6 CHECK HARNESS AND CONNECTOR (A/F RELAY - BODY GROUND)

CHECK HARNESS AND CONNECTOR (A/F RELAY - BODY GROUND)

  1. Remove the A/F relay from the No. 6 engine room relay block.
  2.  Measure the resistance according to the value(s) in the table below.

Standard resistance: Check for open

Standard resistance

REPAIR OR REPLACE HARNESS OR CONNECTOR (A/F RELAY - BATTERY)

7 CHECK HARNESS AND CONNECTOR (A/F RELAY - ECM)

CHECK HARNESS AND CONNECTOR (A/F RELAY - ECM)

  1. Disconnect the A5 or A6 A/F sensor connector.
  2. Disconnect the E10 ECM connector.
  3.  Measure the resistance according to the value(s) in the table below.

Standard resistance: Check for open

Standard resistance

Check for short

Standard resistance

  1. Reconnect the ECM connector.
  2.  Reconnect the A/F sensor connectors.

8 CHECK WHETHER DTC OUTPUT RECURS

  1. Connect the intelligent tester to the DLC3.
  2.  Turn the ignition switch to the ON position.
  3.  Turn the intelligent tester ON.
  4.  Clear the DTCs.
  5.  Start the engine.
  6.  Allow the engine to idle for 1 minute or more.
  7.  Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
  8.  Read the DTCs.

Result

Result

CHECK FOR INTERMITTENT PROBLEMS

Crankshaft Position - Camshaft Position Correlation
DTC P0016 Crankshaft Position - Camshaft Position Correlation (Bank 1 Sensor A) DTC P0017 Crankshaft Position - Camshaft Position Correlation (Bank 1 Sensor B) DTC P0018 Crankshaft Position - Cams ...

Oxygen Sensor Heater Control Circuit Low/ Oxygen Sensor Heater Control Circuit High/ Oxygen Sensor Heater Circuit Malfunction
DTC P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2) DTC P0038 Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2) DTC P0057 Oxygen Sensor Heater Control Circuit Low (Bank ...

Other materials:

Diagnosis system
1. CHECK DLC3  The ECU uses the ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format. NOTICE: *: Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not opera ...

Power back door main switch
INSPECTION 1. INSPECT POWER BACK DOOR MAIN SWITCH Inspect the resistance of the main switch. Resistance If the result is not as specified, replace the switch. Apply battery voltage and check the illuminates. OK HINT: Whether the switch illuminates or not will not affect th ...

Vehicle Speed Signal Circuit between Radio and Navigation Assembly and Combination Meter
DESCRIPTION The radio and navigation assembly receives a vehicle speed signal from the combination meter and information about the GPS antenna, and then adjusts vehicle position. HINT:  A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter. The sig ...

В© 2011-2019 Copyright www.tsienna.net