Diagnosis Description
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Diagnosis Description
INTRODUCTION
The hybrid vehicle control ECU has an on board diagnostic system, which detects malfunctions related to hybrid vehicle control system, sensors, actuators or HV battery systems, and records various diagnostic information relating to the malfunction. The hybrid vehicle control ECU also illuminates the MIL and/or 3 warning lights (Hybrid system warning light, High voltage battery warning light, Charge warning light) in the combination meter. For which light illuminates, Testing and Inspection.
Three-digit information code (INF code) has been provided in the conventional DTC as subset of a primary five-digit code. This enable the troubleshooting procedure to further narrow down a malfunctioning area to identify a problem.
The above information can be checked using procedures listed in the table below.
ONE TRIP DETECTION LOGIC
When a malfunction is detected, DTC and freeze frame data are stored in the hybrid vehicle control ECU memory and illuminates the MIL and/or warning lights on the combination meter. Testing and Inspection, "DTC Index".
TWO TRIP DETECTION LOGIC
Specific on board diagnostic items have the two trip detection logic. When a malfunction is detected for the first time, DTC is not stored in the hybrid vehicle control ECU memory. [1st trip]
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in the hybrid vehicle control ECU memory, and the MIL and/or warning lights in the combination meter illuminates. [2nd trip]
The "trip" in the "Two trip detection logic" means a driving mode in which self-diagnosis is performed during vehicle operation. For the items which have the two trip detection logic, Testing and Inspection.
HOW TO READ DTC
With CONSULT-III
With GST
CONSULT-III or GST (Generic Scan Tool) Examples: P0560, P0A1A, etc.
These DTCs are prescribed by SAE J2012.
(CONSULT-III also displays the malfunctioning component or system.)
DTC of a malfunction is displayed in SELF-DIAGNOSTIC RESULTS mode of CONSULT-III.
HOW TO ERASE DTC
With CONSULT-III
The diagnostic information in the hybrid vehicle control ECU can be erased by selecting "Erase" in the" "SELFDIAG RESULTS" mode with CONSULT-III.
With GST
The diagnostic information in the hybrid vehicle control ECU can be erased by selecting Service $04 with GST.
OBD System Operation Chart
Relationship Between MIL and Detectable Items
- When a malfunction is detected for the first time, DTC is stored in the hybrid vehicle control ECU memory.
- When the same malfunction is detected in two consecutive trips, the DTC and the freeze frame data are stored in the hybrid vehicle control ECU memory for some DTCs.
- The MIL will turn off after the vehicle is driven 3 times (driving pattern B) with no malfunction. The drive is counted only when the recorded driving pattern is met (as stored in the hybrid vehicle control ECU). If another malfunction occurs while counting, the counter will reset.
- The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) without the same malfunction recurring.
Summary Chart
[Driving Pattern A]
- The A counter will be cleared when the malfunction is detected regardless of (1) - (3).
- The A counter will be counted up when (1) - (3) 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 the 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.