Sfi System - P0058

Brand:

Toyota

Model Name:

4Runner GRN210 215 UZN210 215

Manual:

Repair Manual

Section:

2Uz-Fe Engine Control System

Title:

Sfi System

  1. Description

  2. Monitor description

  3. Monitor strategy

  4. Typical enabling conditions

  5. Typical malfunction thresholds

  6. Component operating range

  7. Monitor result

  8. Wiring diagram

  9. Inspection procedure

  10. Inspect heated oxygen sensor (heater resistance)

  11. Inspect efi relay

  12. Inspect ecm (ht1b or ht2b voltage)

  13. Check harness and connector (heated oxygen sensor - efi relay, heated oxygen sensor - ecm)

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 2 Sensor 2)

DTC P0058 Oxygen Sensor Heater Control Circuit High (Bank 2 Sensor 2)


​

DESCRIPTION

HINT:
Sensor 2 refers to the sensor mounted behind the Three-Way Catalyst Converter (TWC) and located far from the engine assembly.
In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a TWC is used. For the most efficient use of the TWC, the air fuel ratio must be precisely controlled so that it is always close to the stoichiometric air fuel level. For the purpose of helping the ECM to deliver accurate air fuel ratio control, a Heated Oxygen (HO2) sensor is used.
The HO2 sensor is located behind the TWC, and detects the oxygen concentration in the exhaust gas. Since the sensor is integrated with the heater that heats the sensing portion, it is possible to detect the oxygen concentration even when the intake air volume is low (the exhaust gas temperature is low).
When the air fuel ratio becomes lean, the oxygen concentration in the exhaust gas is rich. The HO2 sensor informs the ECM that the post-TWC air fuel ratio is lean (low voltage, i.e. less than 0.45 V).
Conversely, when the air fuel ratio is richer than the stoichiometric air fuel level, the oxygen concentration in the exhaust gas becomes lean. The HO2 sensor has the property of changing its output voltage drastically when the air fuel ratio is close to the stoichiometric level.
The ECM uses the supplementary information from the HO2 sensor to determine whether the air fuel ratio after the TWC is rich or lean, and adjusts the fuel injection time accordingly. Thus, if the HO2 sensor is working improperly due to internal malfunctions, the ECM is unable to compensate for deviations in the primary air fuel ratio control.

Open in Heated Oxygen (HO2) sensor heater circuit 4Runner

HINT:
The ECM provides a pulse width modulated control circuit to adjust the current through the heater. The heated oxygen sensor heater circuit uses a relay on the +B side of the circuit.

Open in Heated Oxygen (HO2) sensor heater circuit 4Runner


DTC No.
DTC Detection Condition
Trouble Area
P0037
P0057
Heater current is 0.25 A or less when the heater operates with more than 10.5 V positive battery voltage
  1. Open in Heated Oxygen (HO2) sensor heater circuit
  2. Heated Oxygen (HO2) sensor heater
  3. EFI Relay
  4. ECM
P0038
P0058
When heater operates, heater current exceeds 2.0 A (1 trip detection logic)
  1. Short in HO2 sensor heater circuit
  2. HO2 sensor heater
  3. EFI Relay
  4. ECM
HINT:
  1. Bank 1 refers to the bank that includes No. 1 cylinder.
  2. Bank 2 refers to the bank that does not include No. 1 cylinder.
  3. Sensor 1 refers to the sensor closest to the engine assembly.
  4. Sensor 2 refers to the sensor farthest away from the engine assembly.

MONITOR DESCRIPTION

  1. The sensing position of the Heated Oxygen (HO2) sensor has a zirconia element which is used to detect the oxygen concentration in the exhaust gas. If the zirconia element is at the appropriate temperature, and the difference between the oxygen concentrations surrounding the inside and outside surfaces of the sensor is large, the zirconia element generates voltage signals. In order to increase the oxygen concentration detecting capacity of the zirconia element, the ECM supplements the heat from the exhaust with heat from a heating element inside the sensor. When the current in the sensor heater is outside the standard operating range, the ECM interprets this as a malfunction in the sensor heater and sets a DTC.
  2. Example:
  3. The ECM sets DTC P0038 or P0058 when the current in the HO2 sensor heater is more than 2 A. Conversely, when the heater current is less than 0.3 A, DTC P0037 or P0057 is set.

MONITOR STRATEGY


Related DTCs
P0037: Heated oxygen sensor heater (bank 1) range check (low current)
P0038: Heated oxygen sensor heater (bank 1) range check (high current)
P0057: Heated oxygen sensor heater (bank 2) range check (low current)
P0058: Heated oxygen sensor heater (bank 2) range check (high current)
Required sensors / components
Heated oxygen sensor heater
Required sensors / components
Vehicle speed sensor (VSS)
Frequency of operation
Continuous
Duration
0.3 seconds
MIL operation
Immediate
Sequence of operation
None

TYPICAL ENABLING CONDITIONS


All:
The monitor will run whenever these DTCs are not present
None

P0037, P0057 (Low current):
Battery voltage
10.5 V or more
All heater is turned OFF and intrusive heating is operated when the following conditions are met
Conditions (a) and (b)
(a) Heater
ON
(b) Heater current
Less than 0.3 A
P0038, P0058 (High current):

  1. Case 1:
    Battery voltage
    		10.5 V or more
    Engine
    		Running
    Starter
    		OFF
    Intrusive heating
    		Not operating

    Case 2:
    Battery voltage
    		10.5 V or more
    All heater is turned OFF and intrusive heating is operated when the following conditions are met
    		Conditions (a) and (b)
    (a) Heater
    		ON
    (b) Heater current
    		2 A or more

TYPICAL MALFUNCTION THRESHOLDS


P0037, P0057 (Low current):
HO2S heater current during intrusive heating
Less than 0.3 A (when battery voltage is 10.5 V or more)
P0038, P0058 (High current):

  1. Case 1:
    HO2S heater current
    		2 A or more

    Case 2:
    HO2S heater current during intrusive heating
    		More than 2 A

COMPONENT OPERATING RANGE


HO2S heater current
0.4 to 1 A (at idle, warmed-up engine and +B: 11 to 14 V)

MONITOR RESULT

Refer to CHECKING MONITOR STATUS (Click here) for detailed information.
The test value and test limit information are described as shown in the following table. Check the monitor result and test values after performing the monitor drive pattern (refer to "Confirmation Monitor").
  1. MID (Monitor Identification Data) is assigned to each emissions-related component.
  2. TID (Test Identification Data) is assigned to each test value.
  3. Scaling is used to calculate the test value indicated on generic OBD II scan tools.

    HO2S heater bank 1 sensor 2
    MID
    		TID
    		Scaling
    		Description of Test Value
    		Minimum Test Limit
    		Maximum Test Limit
    $42
    		$90
    		Multiply by 0.001 (A)
    		Maximum sensor heater current
    		Minimum test limit
    		Maximum test limit

    HO2S heater bank 2 sensor 2
    MID
    		TID
    		Scaling
    		Description of Test Value
    		Minimum Test Limit
    		Maximum Test Limit
    $46
    		$90
    		Multiply by 0.001 (A)
    		Maximum sensor heater current
    		Minimum test limit
    		Maximum test limit

WIRING DIAGRAM


Sfi System - P0503 4Runner


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 HEATED OXYGEN SENSOR (HEATER RESISTANCE)
  1. Disconnect the H6 or H8 Heated Oxygen (HO2) sensor connectors. 4Runner

  2. Disconnect the H6 or H8 Heated Oxygen (HO2) sensor connectors.

  1. Measure the resistance of the HO2 sensor connector.

    Standard resistance:
    Tester Connection
    		Specified Condition
    HT (1) - +B (2)
    		11 to 16 Ω at 20°C (68°F)
    HT (1) - E1 (4)
    		10 kΩ or higher

  1. Reconnect the HO2 sensor connectors.



NGnext
REPLACE HEATED OXYGEN SENSOR
OK
next down

2.INSPECT EFI RELAY
  1. Remove the EFI relay from the engine room relay block. 4Runner

  2. Remove the EFI relay from the engine room relay block.

  1. Measure the resistance of the EFI relay.

    Standard resistance:
    Terminal Connection
    		Specified Condition
    3 - 5
    		10 kΩ or higher
    3 - 5
    		Below 1 Ω
    (when battery voltage applied to terminals 1 and 2)

  1. Reinstall the EFI relay.



NGnext
REPLACE EFI RELAY
OK
next down

3.INSPECT ECM (HT1B OR HT2B VOLTAGE)
  1. Turn the ignition switch ON. 4Runner

  2. Turn the ignition switch ON.

  1. Measure the voltage of the E4 and E5 ECM connectors.

    Standard voltage:
    Terminal Connection
    		Specified Condition
    HT1B (E4-1) - Body ground
    		9 to 14 V
    HT2B (E5-5) - Body ground
HINT:
  1. The HT1B means the heated oxygen sensor bank 1 sensor 2.
  2. The HT2B means the heated oxygen sensor bank 2 sensor 2.


OKnext
REPLACE ECM
NG
next down

4.CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - EFI RELAY, HEATED OXYGEN SENSOR - ECM)
  1. Turn the ignition switch OFF. 4Runner

  2. Turn the ignition switch OFF.

  1. Disconnect the H6 or H8 oxygen sensor connectors.

  1. Disconnect the E4 and E5 ECM connectors.

  1. Measure the resistance.

    Standard resistance (Check for open):
    Terminal Connection
    		Specified Condition
    HTL2 (H6-1) - HT1B (E4-1)
    		Below 1 Ω
    HTR2 (H8-1) - HT2B (E5-5)
    		Below 1 Ω
    Standard resistance (Check for short):
    Terminal Connection
    		Specified Condition
    HTL2 (H6-1) or HT1B (E4-1) - Body ground
    		10 kΩ or higher
    HTR2 (H8-1) or HT2B (E5-5) - Body ground
    		10 kΩ or higher

  1. Remove EFI relay from engine room R/B.

  1. Measure the resistance.

    Standard resistance (Check for open):
    Tester Connection
    		Specified Condition
    +B (H6-2) - EFI relay (3)
    		Below 1 Ω
    +B (H8-2) - EFI relay (3)
    Standard resistance (Check for short):
    Tester Connection
    		Specified Condition
    +B (H6-2) or EFI relay (3) - Body ground
    		10 kΩ or higher
    +B (H8-2) or EFI relay (3) - Body ground

  1. Reconnect the ECM connectors.

  1. Reconnect the oxygen sensor connectors.

  1. Reinstall the EFI relay.



NGnext
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
next down
REPLACE ECM