Diagnostic Aids

WARNING: This page is about a different car, the 1995 Ford Windstar. However, it is still accessible from the selected car via links, so may be relevant.

Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:

Wiring harness circuits (BATT+, EAIR, EAIR MONITOR and Ground.
Solid State Relay (SSR).
Electric Air Pump (EAP).
Air injection by-pass solenoid.
Powertrain Control Module (PCM).

Fig 1: AIR Test Circuit & Connector Terminal ID (Windstar)

1) DTC P0412: Check BATT+ At SSR

This DTC indicates EAIR primary circuit failure. Possible causes are as follows:
- EAIR circuit open or short to power.
- AIR by-pass solenoid failure.
- Faulty PCM.
Turn ignition off. Disconnect SSR. Turn ignition on. Measure voltage between SSR connector BATT+ terminal and negative battery terminal. If voltage is 10.5 volts or more, go to next step. If voltage is less than 10.5 volts, go to step 7).

2) Check EAIR Circuit Continuity

Turn ignition off. Leave SSR disconnected. Disconnect AIR by-pass solenoid. Temporarily remove secondary air dedicated fuse. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect EEC-V Breakout Box (014-000950), leaving PCM disconnected. Measure resistance between test pin No. 70 (EAIR) at breakout box and EAIR terminal at SSR connector. If resistance is 5 ohms or more, repair open circuit and repeat QUICK TEST . If resistance is less than 5 ohms, go to next step.

3) Check EAIR Circuit Short To Power

Leave ignition off. Measure resistance between test pin No. 70 and test pins No. 71, 90 and 97 at breakout box. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, repair short circuit and repeat QUICK TEST .

4)

Leave ignition off. Reconnect AIR by-pass solenoid. Measure resistance between test pin No. 70 and test pins No. 71, 90 and 97 at breakout box. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, replace AIR by-pass solenoid and repeat QUICK TEST .

5)

Leave ignition off. Reconnect SSR. Measure resistance between test pin No. 70 and test pins No. 71, 90 and 97 at breakout box. If resistance is more than 10,000 ohms, replace PCM and repeat QUICK TEST . If resistance is 10,000 ohms or less, replace AIR by-pass solenoid and repeat QUICK TEST .
NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 5) to step 7). No test procedures have been omitted.

7) Check BATT+ Circuit Continuity

Leave ignition off. Disconnect SSR. Measure resistance between SSR connector terminal "A" and AIR system dedicated fuse. See Fig 1 . If resistance is less than 5 ohms, replace dedicated fuse and repeat QUICK TEST . If resistance is 5 ohms or more, repair open in BATT+ circuit and repeat QUICK TEST .

8) Check EAIR MONITOR Circuit For Short To Power

Leave ignition off and SSR disconnected. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect EEC-V Breakout Box (014-000950), leaving PCM disconnected. Turn ignition on. Measure voltage between test pin No. 5 at breakout box and chassis ground. If voltage is 10.5 volts or less, go to next step. If voltage is more than 10.5 volts, repair EAIR MONITOR circuit short to power and repeat QUICK TEST .

9) Check EAIR MONITOR Circuit For Short To Power

Turn ignition off. Reconnect SSR connector. Turn ignition on. Measure voltage between test pin No. 5 at breakout box and chassis ground. If voltage is 10.5 volts or more, go to next step. If voltage is less than 10.5 volts, replace PCM and repeat QUICK TEST .

10)

Leave ignition on. Measure voltage between test pin No. 5 at breakout box and chassis ground. Measure voltage between test pin No. 70 at breakout box and chassis ground. If either voltage measurement is 10.5 volts or less, go to next step. If both voltage measurements are more than 10.5 volts, replace SSR and repeat QUICK TEST .

11) Check Air Pump Hoses

Turn ignition off. Inspect hoses between air pump and air control valves. If hoses are damaged or restricted, repair or replace as necessary and repeat QUICK TEST . If hoses are okay, go to next step.

12) Check Air Pump Operation

Leave ignition off. Disconnect air hose from air control valve. Start engine and allow to idle. After a 5 second delay, airflow should be present for 30-90 seconds. If airflow is as specified, go to next step. If airflow is not as specified, go to step 17).

13) Check For Vacuum At Air Control Valve

Leave ignition off. Disconnect vacuum hose from air control valve. Start engine and allow to idle. After about 5 seconds, vacuum should be present for 30-90 seconds. If vacuum is as specified, go to next step. If vacuum is not as specified, go to step 30).

14) Check Air Control Valve

Leave ignition off. Disconnect and plug air tube at air control valve outlet side. Inspect air tubes for damage and repair as necessary. Start engine and allow to idle. After about 5 seconds, airflow should be present at air control valve for 30-90 seconds. If airflow is as specified, go to next step. If airflow is not as specified, replace air control valve and repeat QUICK TEST .
NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 14) to step 17). No test procedures have been omitted.

17) Check Air Pump Operation

Leave ignition off. Disconnect air pump wiring harness connector. Start engine and allow to idle. Measure voltage between connector EAIR MONITOR terminal and ground. See Fig 1 . After about 5 seconds, voltage should be 10.5 volts or more for 20-30 seconds. If airflow is as specified, go to next step. If airflow is not as specified, go to step 21).

18) Check Ground Circuit

Leave ignition off and air pump disconnected. Measure resistance between air pump connector ground terminal and chassis ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in ground circuit and repeat QUICK TEST .

19) Check Air Pump Hoses

Turn ignition off. Inspect air inlet hose. If hose is damaged or restricted, repair or replace as necessary and repeat QUICK TEST . If hose is okay, go to next step.

20) DTC 1413: Check For Voltage At SSR

Leave ignition off. Disconnect SSR. Turn ignition on. Measure voltage between SSR connector BATT+ terminal and chassis ground. If voltage is less than 10.5 volts, go to step 25). If voltage is 10.5 volts or more, go to next step.

21) Check EAIR MONITOR Circuit Voltage

Leave ignition off. Reconnect SSR. Disconnect air pump wiring harness connector. Start engine and allow to idle. Measure voltage between connector EAIR MONITOR terminal and chassis ground. If voltage is more than 10.5 volts and DTC P0411 is present, replace air pump. If voltage is more than 10.5 volts and DTC P0411 is not present, go to step 24). If voltage is 10.5 volts or less, go to next step.

22) Check EAIR MONITOR Circuit Continuity

Turn ignition off. Disconnect SSR. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect EEC-V Breakout Box (014-000950), leaving PCM disconnected. Measure resistance between test pin No. 5 at breakout box and EAIR MONITOR terminal at SSR connector. Measure resistance between EAIR MONITOR terminal at SSR connector and EAIR MONITOR terminal at air pump connector. If both resistance measurements are 5 ohms or more, repair open in EAIR MONITOR circuit and repeat QUICK TEST . If resistance is less than 5 ohms, go to next step.

23) Check EAIR MONITOR Circuit For Short To Ground

Turn ignition off. Leave SSR and air pump disconnected. Measure resistance between test pin No. 5 and test pins No. 51, 76 and 91 at breakout box. If each resistance measurement is more than 10,000 ohms, replace SSR and repeat QUICK TEST . If any resistance measurement is less than 10,000 ohms, repair EAIR MONITOR circuit short to ground and repeat QUICK TEST .

24) Check EAIR MONITOR Circuit Voltage

Leave ignition off. Reconnect air pump. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect EEC-V Breakout Box (014-000950), leaving PCM disconnected. Start engine and allow to idle. Measure voltage between test pin No. 5 and chassis ground. After about 5 seconds, voltage should be 10.5 volts or more. If voltage is as specified, replace PCM and repeat QUICK TEST . If voltage is not as specified, repair open in EAIR MONITOR circuit and repeat QUICK TEST .

25) Check BATT+ Circuit Continuity

Leave ignition off and SSR disconnected. Measure resistance between SSR connector terminal "A" and AIR system dedicated fuse. See Fig 1 . If resistance is less than 5 ohms, replace dedicated fuse and repeat QUICK TEST . If resistance is 5 ohms or more, repair open in BATT+ circuit and repeat QUICK TEST .

26) DTC P1414: Check EAIR MONITOR Circuit Continuity

Turn ignition off. Disconnect air pump and SSR wiring harness connectors. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect EEC-V Breakout Box (014-000950), leaving PCM disconnected. Measure resistance between test pin No. 5 at breakout box and EAIR MONITOR terminal at air pump connector. If resistance is 5 ohms or more, repair open in EAIR MONITOR circuit and repeat QUICK TEST . If resistance is less than 5 ohms, go to next step.

27)

Leave ignition off and air pump disconnected. Measure resistance between air pump terminals. If resistance is 0.5-5.0 ohms, go to next step. If resistance is not 0.5-5.0 ohms, replace air pump and repeat QUICK TEST .

28) Check EAIR Circuit For Short To Ground

Turn ignition off. Leave SSR disconnected. Disconnect air injection by-pass solenoid. Measure resistance between test pin No. 70 and test pins No. 51, 76 and 91 at breakout box. If each resistance measurement is 10,000 ohms or more, go to next step. If any resistance measurement is less than 10,000 ohms, repair EAIR circuit short to ground and repeat QUICK TEST .

29) Check EAIR Monitor Circuit For Short To Power

Leave ignition off and SSR disconnected. Reconnect air pump. Turn ignition on. Measure voltage between test pin No. 5 at breakout box and chassis ground. If voltage is 5 volts or more, repair EAIR MONITOR circuit short to power and repeat QUICK TEST . If voltage is less than 5 volts, replace PCM and repeat QUICK TEST .

30) Check Vacuum Hoses

Turn ignition off. Disconnect vacuum hose from air injection by-pass solenoid. Connect vacuum hose to vacuum pump. Start engine and allow to idle. If vacuum is 15 in. Hg or more at idle, reconnect vacuum hose to air injection by-pass solenoid and go to next step. If vacuum is less than 15 in. Hg, replace vacuum hose and repeat QUICK TEST .

31) Check Air By-Pass Solenoid

Disconnect air injection by-pass solenoid wiring harness connector. Connect scan tester to DLC. Turn ignition on. Using scan tester, access Output Test Mode (OTM). Connect voltmeter to air injection by-pass solenoid connector. Observe voltmeter while operating throttle. If voltage cycles 0.5 volt or more, go to next step. If voltage does not cycle 0.5 volt or more, go to step 35).

32)

Remain in OTM. Reconnect air injection by-pass solenoid wiring harness connector. Disconnect vacuum hose from air injection by-pass solenoid. Connect vacuum hose to vacuum pump. Apply 16 in Hg. to solenoid. Apply and release throttle. If vacuum releases as throttle cycles, repair vacuum hose between solenoid and air control valve. If vacuum does not release as throttle cycles, check solenoid vacuum supply hose. If hose is okay, replace air injection by-pass solenoid hose.
NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 32) to step 35). No test procedures have been omitted.

35) Check Air By-Pass Solenoid Resistance

Turn ignition off. Disconnect air injection by-pass solenoid wiring harness connector. Measure resistance between connector terminals. If resistance is 50-100 ohms, go to next step. If resistance is not 50-100 ohms, replace air injection by-pass solenoid.

36) Check BATT+ Circuit Voltage

Leave air injection by-pass solenoid disconnected. Turn ignition on. Measure voltage between connector BATT+ terminal and negative battery terminal. If voltage is 10.5 volts or more, go to next step. If voltage is less than 10.5 volts, repair open in BATT+ circuit and repeat QUICK TEST .

37) Check EAIR Circuit Continuity

Leave air injection by-pass solenoid disconnected. Turn ignition off. Disconnect SSR wiring harness connector. Disconnect PCM 104-pin connector. Inspect for damaged pins and repair if necessary. Connect EEC-V Breakout Box (014-000950), leaving PCM disconnected. Measure resistance between test pin No. 70 at breakout box and EAIR terminal at air pump connector. If resistance is 5 ohms or more, repair open in EAIR circuit and repeat QUICK TEST . If resistance is less than 5 ohms, go to next step.

38) Check EAIR Circuit For Short To Ground

Turn ignition off. Leave air injection by-pass solenoid and SSR disconnected. Measure resistance between test pin No. 70 and test pins No. 51, 76 and 91 at breakout box. If each resistance measurement is 10,000 ohms or more, go to next step. If any resistance measurement is less than 10,000 ohms, repair EAIR circuit short to ground and repeat QUICK TEST .

39) Check EAIR Circuit For Short To Power

Leave ignition off. Leave air injection by-pass solenoid and SSR disconnected. Measure resistance between test pin No. 70 and test pins No. 71 and 97 at breakout box. If each resistance measurement is 10,000 ohms or more, replace PCM and repeat QUICK TEST .