DTC P1680 [13B-MSP]

DTC REFERENCE CHART

DTC P1680	OCV circuit low input
DETECTION CONDITION	The PCM monitors input voltage from the OCV. If the voltage of the OCV input terminal is less than the specification for 1 s when the battery voltage is more than 10 V , the PCM determines the OCV circuit voltage is low. Diagnostic support note This is a continuous monitor (Other.) The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle. FREEZE FRAME DATA is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	Connector or terminal malfunction Open circuit in wiring harness between main relay terminal C and OCV terminal B Short to ground in wiring harness between main relay terminal C and OCV terminal B Short to ground in wiring harness between OCV terminal A and PCM terminal 2E Open circuit in wiring harness between OCV terminal A and PCM terminal 2E OCV malfunction PCM malfunction
Courtesy of MAZDA MOTORS CORP.

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED Have FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Verify related Service Bulletins and/or on-line repair information availability. Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT OCV CONNECTOR FOR POOR CONNECTION Turn the ignition switch off. Disconnect the OCV connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion.) Is there any malfunction?	Yes	Repair or replace the terminal, then go to Step 9.
3		No	Go to the next step.
4	INSPECT OCV POWER CIRCUIT FOR OPEN CIRCUIT OR SHORT TO GROUND Turn the ignition switch to the ON position (engine off.) Measure the voltage between OCV terminal B (wiring harness-side) and body ground. Is the voltage B+ ?	Yes	Go to the next step.
4		No	Repair or replace the wiring harness for a possible open circuit or short to ground, then go to Step 9.
5	INSPECT OCV CONTROL CIRCUIT FOR SHORT TO GROUND Turn the ignition switch off. Inspect for continuity between OCV terminal A (wiring harness-side) and body ground. Is there continuity?	Yes	Repair or replace the wiring harness for a possible short to ground, then go to Step 9.
5		No	Go to the next step.
6	INSPECT OCV CONTROL CIRCUIT FOR OPEN CIRCUIT Turn the ignition switch off. Inspect for continuity between OCV terminal A (wiring harness-side) and PCM terminal 2E (wiring harness-side.) Is there continuity?	Yes	Go to the next step.
6		No	Repair or replace the wiring harness for a possible open circuit, then go to Step 9.
7	INSPECT PCM CONNECTOR FOR POOR CONNECTION Turn the ignition switch off. Disconnect the PCM connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion.) Is there any malfunction?	Yes	Repair or replace the terminal, then go to Step 9.
7		No	Go to the next step.
8	INSPECT OCV Inspect the OCV. (See OIL CONTROL VALVE (OCV) INSPECTION [13B-MSP] .) Is there any malfunction?	Yes	Replace the OCV, then go to the next step. (See OIL CONTROL VALVE (OCV) REMOVAL/INSTALLATION [13B-MSP] .)
8		No	Go to the next step.
9	VERIFY TROUBLESHOOTING OF DTC P1680 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. Start the engine. Is the same DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [13B-MSP] .)
9		No	Go to the next step.
10	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE [13B-MSP] .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [13B-MSP] .)
10		No	DTC troubleshooting completed.