DTC P1686: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes
WARNING: This page is about a different car, the 2008 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.
DTC P1686 DETECTION & CONDITION POSSIBLE CAUSES

DTC P1686 Metering oil pump control circuit low flow side problem
DETECTION CONDITION 
  • The PCM monitors the input signal from the metering oil pump switch when the metering oil pump stepping motor is more than the standard step. If the input signal is off, the PCM determines that the metering oil pump control circuit has a problem on the low flow side.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle.
  • PENDING CODE is available if the PCM detects the above malfunction condition.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Metering oil pump malfunction
  • Metering oil pump switch malfunction
  • Connector or terminal malfunction
  • Open circuit in wiring harness between main relay terminal C and metering oil pump terminal C
  • Short to ground in wiring harness between main relay terminal C and metering oil pump terminal C
  • Open circuit in wiring harness between main relay terminal C and metering oil pump terminal D
  • Short to ground in wiring harness between main relay terminal C and metering oil pump terminal D
  • Open circuit in wiring harness between metering oil pump terminal A and PCM terminal 2V
  • Short to ground in wiring harness between metering oil pump terminal A and PCM terminal 2V
  • Open circuit in wiring harness between metering oil pump terminal E and PCM terminal 2W
  • Short to ground in wiring harness between metering oil pump terminal E and PCM terminal 2W
  • Open circuit in wiring harness between metering oil pump terminal B and PCM terminal 2Y
  • Short to ground in wiring harness between metering oil pump terminal B and PCM terminal 2Y
  • Open circuit in wiring harness between metering oil pump terminal F and PCM terminal 2AB
  • Short to ground in wiring harness between metering oil pump terminal F and PCM terminal 2AB
  • Open circuit in wiring harness between metering oil pump switch terminal A and PCM terminal 2N
  • Open circuit in wiring harness between metering oil pump switch terminal C and PCM terminal 1U
  • PCM malfunction
G04562672Courtesy of MAZDA MOTORS CORP.
RENDER: 1.0x

NO RELATED

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