Drive Cycle - Subaru Legacy 2004 Service Manual

ENGINE (DIAGNOSTICS)

12.Drive Cycle

A: PROCEDURE
For the troubleshooting, there are three driving patterns. By driving the vehicle with specified pattern, follow-
ing trouble items could be diagnosed. After the repair of following trouble items, be sure to drive the vehicle
with specified patterns to check the trouble was repaired correctly.
1. PREPARATION FOR DRIVE CYCLE
1) Check battery voltage is more than 12 V and fuel remains half [20 — 40 2 (5.3 — 10.6 US gal, 4.4 — 8.8
Imp gal)].
2) After performing the diagnostics and clearing the memory, check for any remaining unresolved trouble da-
ta: <Ref. to EN(H6DO)(diag)-40, Clear Memory Mode.>
3) Separate the test mode connector.
NOTE:
• Perform the diagnosis after warming up the engine except the engine coolant temperature was specified
at engine start.
• Perform the diagnosis twice if the DTC marked with *. After completing the first diagnosis, stop the engine
and perform second diagnosis in same condition.
2. DRIVE THE VEHICLE WITH 80 KM/H (50 MPH) FOR 20 MINUTES, AND THEN IDLE THE EN-
GINE FOR A MINUTE.
DTC
*P0125 Insufficient Coolant Temperature For Closed Loop Fuel Control
O Sensor Circuit Slow Response (Bank 1 Sensor 1)
*P0133
2
O Sensor Circuit Slow Response (Bank 2 Sensor 1)
*P0153
2
*P0420 Catalyst System Efficiency Below Threshold (Bank 1)
3. 10 MINUTES IDLING
NOTE:
Drive the vehicle in more than 10 km/h (6 MPH) before diagnosis.
DTC
*P0030 HO2S Heater Control Circuit (Bank 1 Sensor 1)
*P0050 HO2S Heater Control Circuit (Bank 2 Sensor 1)
*P0459 Evaporative Emission Control System Purge Control Valve Circuit High
Drive Cycle
Item
Item
EN(H6DO)(diag)-38
On condition
Engine coolant temperature at
engine start is 20!C (68!F) or
less.
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On condition
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