Part 1
2ZR-FE ENGINE CONTROL: SFI SYSTEM: P1603, P1605; Engine Stall History; 2013 MY Corolla [07/2012 -]
P1605 - Rough Idling
DESCRIPTION
P1603
After starting the engine, this DTC is stored when the engine stops without the ignition switch being operated.
Using the Techstream, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.
It is necessary to check if the vehicle has ran out of fuel before performing troubleshooting, as this DTC is also stored when the engine stalls due to running out of fuel.
P1605
This DTC is stored if the engine speed drops below the set speed.
Using the Techstream, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.
It is necessary to check if the vehicle ran out of fuel before performing troubleshooting, as this DTC is also stored when idling is unstable due to running out of fuel.
* *1: for Automatic transaxle models
1. Reference waveforms showing a normal cold engine start
2. Reference waveforms showing a normal warm engine start
3. Reference values when there is an air leak in the intake system during rough idling
Freeze Frame Data P1605 Rough Idling
WIRING DIAGRAM
Refer to DTC P0351 for ignition coil assembly circuit P0351.
Refer to DTC P0443 for purge VSV circuit (for Mexico models) P0443.
Refer to DTC P2195 for air fuel ratio sensor circuit P2195.
Refer EVAP System for purge VSV circuit (except Mexico models) EVAP System.
Refer to Fuel Pump Control Circuit Fuel Pump Control Circuit.
Refer to Fuel Injector Circuit Fuel Injector Circuit.
INSPECTION PROCEDURE
HINT
* In contrast to normal malfunction diagnosis for components, circuits and systems, DTCs P1603 and P1605 are used to determine the malfunctioning area from the problem symptoms and freeze frame data when the user mentions problems such as engine stall.
As these DTCs can be stored as a result of certain user actions, even if these DTCs are output, if the customer makes no mention of problems, clear these DTCs without performing any troubleshooting and return the vehicle to the customer.
* If any other DTCs are output, perform troubleshooting for those DTCs first.
* Use any information from the customer problem analysis about the condition of the vehicle at the time when the problem occurred (how the engine stopped, conditions when the engine was restarted, etc.) as a reference.
* Read freeze frame data using the Techstream. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.
* When confirming the freeze frame data, be sure to check all 5 sets of freeze frame data Freeze Frame Data.
* When DTC P1603 (Engine Stall History) is stored, DTC P1605 (Rough Idling) is also stored. When confirming freeze frame data, check DTC P1605. The ECM stores DTC P1605 first. Therefore, 5 sets of freeze frame data can be confirmed through DTC P1605, enabling the technician to obtain more information.
* When confirming freeze frame data, if there are multiple items related to the cause of the malfunction, perform troubleshooting for all related items.
* Try to operate the vehicle under the conditions recorded in the freeze frame data which were present when the malfunction occurred. Confirm the data at this time and the data when the engine is idling (engine warmed up and no load) and compare these data with the freeze frame data.
* Inspections take into account the fact that the malfunction may not have reoccurred and place emphasis on checking the vehicle conditions present at the time when the malfunction occurred.
* When performing inspections, jiggle the relevant wire harnesses and connectors in an attempt to reproduce malfunctions that do not always occur.
Inspection flow:
Using freeze frame data, narrow down the parts to be inspected according to the vehicle conditions at the time when the malfunction occurred.
P1603:
1:
* If the engine stalled when the intake air volume was low (during idling or deceleration), there may be a decrease in torque due to an incorrect air fuel ratio, etc.
* If the engine stalled when the intake air volume was high (during driving or acceleration), there may be a major malfunction such as continuous misfire due to ignition stoppage, fuel injection stoppage, etc. and the torque drops to zero.
2:
* If the engine speed decreased slowly, there may have been a decrease in torque due to an air fuel ratio that was incorrect (by approximately 20 to 30%), etc.
* If the engine speed decreased rapidly, there may have been a malfunction such as when the engine misfires almost continuously due to ignition stoppage, fuel injection stoppage, etc., or when the external load increases due to an external part malfunctioning.
3:
* If the air fuel ratio is abnormal, there may have been an intake air leak, sensor malfunction, or fuel supply problem.
* If the vehicle was normal, the air volume may have been insufficient or the ignition timing may have been incorrect.
P1603 inspection flow: Narrow down the parts to be inspected according to the vehicle conditions at the time when the malfunction occurred (freeze frame data).
P1605:
1:
* If the engine speed decreased slowly, there may have been a decrease in torque due to an air fuel ratio that was incorrect (by approximately 20 to 30%), etc.
* If the engine speed decreased rapidly, there may have been a malfunction such as when the engine misfires almost continuously due to ignition stoppage, fuel injection stoppage, etc., or when the external load increases due to an external part malfunctioning.
2:
* If the air fuel ratio is abnormal, there may have been an intake air leak, sensor malfunction, or fuel supply problem.
* If the vehicle was normal, the air volume may have been insufficient or the ignition timing may have been incorrect.
P1605 inspection flow: Narrow down the parts to be inspected according to the vehicle conditions at the time when the malfunction occurred (freeze frame data).
* *1: for Automatic transaxle models
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
1. CHECK FOR ANY OTHER DTCS OUTPUT
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(e) Read the DTCs Reading and Clearing Diagnostic Trouble Codes.
Result
HINT
If any DTCs other than P1603 or P1605 are output, troubleshoot those DTCs first.
B -- GO TO DTC CHART SFI System
A -- Continue to next step.
2. CHECK FREEZE FRAME DATA
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Using the Techstream, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Freeze Frame Data.
OK:
Immobiliser Fuel Cut is OFF.
Result
B -- READ FREEZE FRAME DATA
A -- Continue to next step.
3. CHECK ENGINE IMMOBILISER SYSTEM
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Idle the engine
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Immobiliser Communication and Immobiliser Fuel Cut.
(e) Check the Data List indication.
Standard
Result
B -- CHECK ENGINE IMMOBILISER SYSTEM How to Proceed With Troubleshooting
C -- CHECK ENGINE IMMOBILISER SYSTEM How to Proceed With Troubleshooting
A -- Continue to next step.
4. READ FREEZE FRAME DATA
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Using the Techstream, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Freeze Frame Data.
Result
HINT
* *1: A rapid decrease in engine speed may be caused by an electrical fault in the shared wiring of all or a number of cylinders, an increase in load from external parts, etc. The engine speed is considered to have decreased rapidly if either of the following conditions applies.
Otherwise, the engine speed is considered to have decreased slowly.
(1) In the freeze frame data, the decrease in engine speed from #3 to #5 is 400 rpm or more.
(2) In the freeze frame data, the engine speed at #5 is 120 rpm or less.
* If the vehicle speed is 30 km/h (19 mph) or less and the difference between Engine Speed and SPD (NT) is 100 rpm or less, inspect the automatic transmission. (Depending on the rate of vehicle deceleration, the engine speed may have decreased due to the A/T lock-up release being late.)
* *2: When a DTC is stored, feedback compensation increases because the air fuel ratio is determined to be lean.
* *3: When a DTC is stored, feedback compensation decreases because the air fuel ratio is determined to be rich.
* *4: This item should be checked when DTC P1603 is output and is not necessary to check when only P1605 is output.
B -- CHECK IGNITION SYSTEM
C -- CHECK IGNITION SYSTEM
D -- CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL INJECTOR ASSEMBLY)
E -- CHECK FREEZE FRAME DATA
A -- Continue to next step.