Power Relay Control / Coil (Dtc 686, 687); Dtc 686-Power Relay Ground Short; Dtc 687-Power Relay Coil Short-To-Power - Kubota WG1605-E3 Diagnostic Manual

WG1605-G-E3,WG1605-L-E3,WG1605-GL-E3, DM

(19) Power Relay Control / Coil (DTC 686, 687)

DTC 686-Power Relay Ground Short

• Hardware: Power Relay Pull in Coil
• Enabling Conditions: Key On, Engine Off
• Set Conditions: Power relay coil output shorted to ground for more than 10 samples of circuit
• Corrective Action(s): Illuminate MIL
• Non-emissions related fault
• Possible Causes: Short to ground in relay pull in coil, short to ground in relay driver circuit in wire harness, faulty
ECM

DTC 687-Power Relay Coil Short-To-Power

• Hardware: Power Relay Pull in Coil
• Enabling Conditions: Key On, Engine Off
• Set Conditions: Power relay coil output short to power/voltage
• Corrective Action(s): Illuminate MIL
• Non-emissions related fault
• Possible Causes: Shorted relay pull in coil, relay driver circuit shorted to voltage in wire harness
The fault of DTC 686 sets if the output for the power relay is detected as being shorted to ground. If this fault is
active and the high-side of the power relay is supplied, the following components will have power until the relay or
high-side power is removed: CMP sensor, CKP sensor, both O2 sensors, the DEPR (if attached) and all fuel injectors
(gasoline engines).
The fault of DTC 687 sets if the output for the power relay is detected as shorted to power.
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ECM SYSTEM
KiSC issued 12, 2016 A