Generator/Regulator System Malfunction

NOTE: The following test procedures are for DTCs P062, P1246, P1630, P1631 and P1634.

Fig 1: Generator/Regulator System Malfunction Detection Condition Possible Cause

Courtesy of MAZDA MOTORS CORP.

GENERATOR/REGULATOR SYSTEM MALFUNCTION INSPECTION/ACTION CHART

STEP	INSPECTION		ACTION
1	Was PCM Quick Test performed?	Yes	Go to next step.
1	Was PCM Quick Test performed?	No	Perform PCM Quick Test. See PCM QUICK TEST .
2	VERIFY GENERATOR DRIVE CYCLE Check generator drive belt condition and tension. Start engine and verify generator is turning. Is everything OK?	Yes	Go to next step.
2		No	Repair or replace parts. Go to step 11.
3	VERIFY CHARGING SYSTEM IS EEC CONTROLLED Key OFF. Disconnect battery cables at battery. Disconnect generator harness connector and measure resistance between BATT-SENSE and GEN-COM pins at the generator. Is resistance between 950 and 1050 ohms?	Yes	Go to next step.
3		No	Replace generator/regulator assembly. GENERATOR . Go to step 11.
4	CHECK BATTERY-SENSE VOLTAGE AT BATTERY Reconnect battery cables. Measure voltage at generator/regulator harness connector between BATT-SENSE and chassis ground. Is battery voltage of battery-sense circuit within plus or minus 0.5 volts of battery voltage?	Yes	Go to next step.
4		No	Repair BATT-SENSE circuit. Go to step 11.
5	CHECK GENERATOR FAILURE MODE Turn off all electrical loads. Access GFS PID. Start engine and increase engine speed to 2000 rpm. Perform wiggle test. Is a failure indicated?	Yes	Go to next step.
5		No	Repair or replace parts. Go to step 11.
6	CHECK GEN-MON AND GEN-COM CIRCUIT FOR SHORT TO POWER Key OFF. Disconnect generator. Disconnect PCM. Install Breakout Box, leave PCM disconnected. Key ON, Engine OFF (KOEO), Engine OFF. Measure voltage between PCM test pin E7 (GEN-COM) and chassis ground. Measure voltage between PCM test pin E16 (GEN-MON) and chassis ground. Key OFF. Is each voltage greater than 0.5 ohms?	Yes	Repair short circuit. Go to step 11.
6		No	Go to next step.
7	CHECK GEN-MON AND GEN-COM CIRCUIT FOR SHORT TO GROUND Measure resistance between PCM test pin E7 (GEN-COM) and chassis ground. Measure resistance between PCM test pin E16 (GEN-MON) and chassis ground. Is each resistance greater than 10K ohms?	Yes	Go to next step.
7		No	Repair short circuit. Go to step 11.
8	CHECK GEN-MON AND GEN-COM CIRCUIT FOR OPEN Measure resistance of GEN-COM circuit between PCM test pin E7 and generator/regulator harness connector. Measure resistance of GEN-MON circuit between PCM test pin E16 and generator/regulator harness connector. Is each resistance less than 5.0 ohms?	Yes	Go to next step.
8		No	Repair open circuit. Go to step 11.
9	CHECK GENERATOR MONITOR SIGNAL Key ON, Engine Running (KOER). Access GF PID. Is duty cycle between 6-98%?	Yes	Go to next step.
9		No	Replace generator/regulator assembly. GENERATOR . Go to step 11.
10	CHECK GENERATOR COMMUNICATOR SIGNAL Key ON, Engine Running (KOER). Access GENFDC PID. Toggle load on and off (headlights). Is duty cycle between 0-99% range?	Yes	Go to next step.
10		No	Replace generator/regulator assembly. GENERATOR . Go to next step.
11	VERIFY TROUBLESHOOTING OF DTCs COMPLETED Make sure to reconnect all disconnected connectors. Clear DTCs from PCM memory using WDS or equivalent tester generic OBD II function. Perform PCM Quick Test. See PCM QUICK TEST . Is any DTC present?	Yes	Replace PCM, see POWERTRAIN CONTROL MODULE (PCM) . Repeat PCM Quick Test. See PCM QUICK TEST .
11		No	If any other DTC is present, go to applicable DTC inspection. If no DTC is present, troubleshooting complete.