How To Use Tests

1) Ensure all non-EEC-IV related faults found while performing steps in BASIC TESTING article have been corrected. DO NOT perform any TEST unless instructed by a QUICK TEST procedure. Follow each test step in order until fault is found. When more than one code is retrieved, start with first code displayed.

2) TESTS ensure electrical circuits are okay before sensors or other components are replaced. Always test circuits for continuity between sensor and ECA. Test all circuits for short to power, opens or short to ground. Voltage Reference (VREF) and Voltage Power (VPWR) circuits should be tested with ignition on unless otherwise specified in TESTS.

3) DO NOT measure voltage or resistance at ECA. DO NOT connect any test light unless specified in testing procedure. Make all measurements by probing rear of connector. Isolate both ends of circuit and turn ignition off when checking continuity, unless instructed otherwise.

4) Disconnect solenoids and switches from harness before measuring continuity and resistance or applying voltage. After each repair, check all component connections and repeat QUICK TEST .

TEST INDEX

Circuit Test Title	...	Circuit Tested
No-Start & Voltage Tests	...	...
...	AA	No Start (EDIS)
...	B	Vehicle Battery
...	C	Reference Voltage
Input Sensor Tests	...	...
...	DA	ACT/ECT Sensor
...	DC	Mass Airflow Sensor
...	DF	Barometric Pressure Sensor
...	DH	Throttle Position Sensor
...	DP	Vehicle Speed Sensor
Additional Input Component Tests	...	...
...	FA	Neutral Drive Input
...	FD	Brake On-Off (BOO) Switch
Fuel Control System Tests	...	...
...	H	Fuel Control
...	J	Fuel Pump Circuit
ECA (Processor) Output Tests	...	...
...	KD	Canister Purge
...	KE	Idle Speed Control
...	KM	WAC & A/C Demand Switch
...	KP	Octane Adjust
...	M	Dynamic Response Test
...	ML	CHECK ENGINE Light
...	N	Ignition Diagnostic Monitor (IDM)
...	P	Spark Timing Check
...	QA	No Codes/Codes Not Listed
...	QB	Continuous Memory Service Code 15 Or 512
...	QC	Output State Check Not Functioning
...	QD	Re-Initialization Check
...	S	System Check
...	TB	Transmission A4LD

NOTE: In following tests, circuit diagrams and illustrations are courtesy of Mazda Motors Corp.