Exhaust Gas Recirculation (EGR) System Monitor (P0400)

Test requirements/procedure

1. All of the following requirements should be met when carrying out a drive test.
   1. Engine coolant temperature: 80°C (176°F) or more (Engine fully warmed up)
   2. Atmospheric temperature: 5°C (41°F) or more
   3. Condition of A/T:
      • Selector lever position: D range
      • Overdrive switch: ON
      • Pattern select switch: OFF
   4. A/C switch: OFF
2. One trip monitor will be completed by driving according to the steps below (from start to switch off). It will take approx. 10 minutes.
   1. After warming up, turn off the ignition switch.
   2. Start the engine, and accelerate to 56 - 64 km/h (35 - 40 mph).
   3. Close the throttle fully from 2000 - 3000 r/min with the clutch engaged , and then decelerate to 900 r/min without applying brakes. Moreover, do not turn the steering wheel or switch on or off the lights.
   4. Accelerate to 56 - 64 km/h (35 - 40 mph), and continue driving for 20 seconds. (After 1st monitor (deceleration), wait for 20 seconds or more until the next monitor (deceleration) starts). Then repeat 3 and 4 steps eight times.
   5. Decelerate and stop. Then turn off the ignition switch.

Fig 1: Drive Cycle Pattern For Exhaust Gas Recirculation (EGR) System Monitor

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.