Nissan Titan. Manual - part 185

DIAGNOSIS SYSTEM (ECM)

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• The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.

• The B counter will be counted up when driving pattern B is satisfied without any malfunction.

• The MIL will turn OFF when the B counter reaches 3. (*2 in “OBD SYSTEM OPERATION CHART”)

<Driving Pattern C>

Driving pattern C means operating vehicle as per the following:

The following conditions should be satisfied at the same time:

Engine speed: (Engine speed in the freeze frame data) 

±375 rpm

Calculated load value: (Calculated load value in the freeze frame data) x (1

±0.1) [%]

Engine coolant temperature (T) condition:

• When the freeze frame data shows lower than 70

°C (158°F), T should be lower than 70°C (158°F).

• When the freeze frame data shows higher than or equal to 70

°C (158°F), T should be higher than or equal to

70

°C (158°F).

Example:

If the stored freeze frame data is as per the following:

Engine speed: 850 rpm, Calculated load value: 30%, Engine coolant temperature: 80

°C (176°F)

To be satisfied with driving pattern C, the vehicle should run under the following conditions:

Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70

°C

(158

°F)

• The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.

• The C counter will be counted up when vehicle conditions above are satisfied without the same malfunction.

• The DTC will not be displayed after C counter reaches 80.

• The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is

stored in ECM.

Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns Except For “Misfire <Exhaust
Quality Deterioration>”, “Fuel Injection System”

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DIAGNOSIS SYSTEM (ECM)

*1: When the same malfunction is de-

tected in two consecutive trips, MIL 
will light up.

*2: MIL will turn OFF after vehicle is driv-

en 3 times (pattern B) without any 
malfunctions.

*3: When the same malfunction is de-

tected in two consecutive trips, the 
DTC and the freeze frame data will be 
stored in ECM.

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DIAGNOSIS SYSTEM (ECM)

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Explanation for Driving Patterns Except for “Misfire <Exhaust Quality Deterioration>”, “Fuel Injection
System”

<Driving Pattern A>

• The A counter will be cleared when the malfunction is detected regardless of (1) - (4).

• The A counter will be counted up when (1) - (4) are satisfied without the same malfunction.

• The DTC will not be displayed after the A counter reaches 40.

<Driving Pattern B>

Driving pattern B means operating vehicle operation as per the following:

All components and systems should be monitored at least once by the OBD system.

• The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.

• The B counter will be counted up when driving pattern B is satisfied without any malfunctions.

• The MIL will turn OFF when the B counter reaches 3 (*2 in OBD SYSTEM OPERATION CHART).

DIAGNOSIS DESCRIPTION : Driving Pattern

INFOID:0000000009886507

CAUTION:

Always drive at a safe speed.

DRIVING PATTERN A

Driving pattern A means a trip satisfying the following conditions.

• Engine speed reaches 400 rpm or more.

• Engine coolant temperature rises by 20

°C (36°F) or more after starting the engine.

• Engine coolant temperature reaches 70

°C (158°F) or more.

• The ignition switch is turned from ON to OFF.

NOTE:

• When the same malfunction is detected regardless of driving conditions, reset the counter of driving pattern

A.

• When the above conditions are satisfied without detecting the same malfunction, reset the counter of driving

pattern A.

DRIVING PATTERN B

Driving pattern B means a trip satisfying the following conditions.

• Engine speed reaches 400 rpm or more.

• Engine coolant temperature reaches 70

°C (158°F) or more.

*4: The DTC and the freeze frame data 

will not be displayed any longer after 
vehicle is driven 40 times (pattern A) 
without the same malfunction.
(The DTC and the freeze frame data 
still remain in ECM.)

*5: When a malfunction is detected for 

the first time, the 1st trip DTC and the 
1st trip freeze frame data will be 
stored in ECM.

*6: 1st trip DTC will be cleared after vehi-

cle is driven once (pattern B) without 
the same malfunction.

*7: When the same malfunction is de-

tected in the 2nd trip, the 1st trip 
freeze frame data will be cleared.

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• Vehicle speed of 70 – 120 km/h (44 – 75 MPH) is maintained for 60 seconds or more under the control of

closed loop.

• Vehicle speed of 30 – 60 km/h (19 – 37 MPH) is maintained for 10 seconds or more under the control of

closed loop.

• Under the closed loop control condition, the following state reaches 12 seconds or more in total: Vehicle

speed of 4 km/h (2 MPH) or less with idling condition.

• The state of driving at 10 km/h (7 MPH) or more reaches 10 minutes or more in total.

• A lapse of 22 minutes or more after engine start.

NOTE:

• Drive the vehicle at a constant velocity.

• When the same malfunction is detected regardless of driving conditions, reset the counter of driving pattern

B.

• When the above conditions are satisfied without detecting the same malfunction, reset the counter of driving

pattern B.

DRIVING PATTERN C

Driving pattern C means operating vehicle as per the following:

The following conditions should be satisfied at the same time:

Engine speed: (Engine speed in the freeze frame data) 

±375 rpm

Calculated load value: (Calculated load value in the freeze frame data) x (1

±0.1) [%]

Engine coolant temperature condition:

• When the freeze frame data shows lower than 70

°C (158°F), engine coolant temperature should be lower

than 70

°C (158°F).

• When the freeze frame data shows higher than or equal to 70

°C (158°F), engine coolant temperature should

be higher than or equal to 70

°C (158°F).

NOTE:

• When the same malfunction is detected regardless of the above vehicle conditions, reset the counter of driv-

ing pattern C.

• When the above conditions are satisfied without detecting the same malfunction, reset the counter of driving

pattern C.

• The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is

stored in ECM.

DRIVING PATTERN D

Driving pattern D means a trip satisfying the following conditions.

• The state of driving at 40 km/h (25 MPH) reaches 300 seconds or more in total.

• Idle speed lasts 30 seconds or more.

• A lapse of 600 seconds or more after engine start.

NOTE:

• When the same malfunction is detected regardless of driving conditions, reset the counter of driving pattern

D.

• When the above conditions are satisfied without detecting the same malfunction, reset the counter of driving

pattern D.

DIAGNOSIS DESCRIPTION : System Readiness Test (SRT) Code

INFOID:0000000009886508

System Readiness Test (SRT) code is specified in Service $01 of SAE J1979/ISO 15031-5.

As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of

SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-

ponents. Completion must be verified in order for the emissions inspection to proceed.

If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use

the information in this Service Manual to set the SRT to “CMPLT”.

In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT

status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains

“CMPLT” until the self-diagnosis memory is erased.

Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's

normal driving pattern; the SRT will indicate “INCMP” for these items.

NOTE:

The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-

ory power supply is interrupted for several hours.