Test Pin Identification - Mustang

5.0L SPFI-MA TEST PIN WIRE COLOR I.D.

Application	Wire Color
Pin 26 (VREF)	Brown/White
Pin 40 (PWR GND)	Black/Light Green
Pin 45 (BP)	Light Green/Black
Pin 46 (SIG RTN)	Gray/Red
Pin 60 (PWR GND)	Black/White

MAP SENSOR SPECIFICATIONS

Manifold Vacuum In. Hg	Frequency Hz
0	159
3	150
6	141
9	133
12	125
15	117
18	109
21	102
24	95
27	88
30	80

MAP/BP SENSOR SPECIFICATIONS

Barometric Pressure In. Hg	Frequency Hz
17.1	122.4
18.3	125.5
19.5	128.7
20.7	131.9
21.8	135.1
23.0	138.3
24.2	141.8
25.4	145.4
26.6	148.9
27.7	152.5
28.9	156.1
30.1	159.6
31.0	162.4

1) Code 22/126: Check For Power to MAP/BP Sensor Code 22/126 indicates MAP/BP sensor is out of self-test voltage range (1.4-1.6 volts). The following are possible causes of this code:

MAP/BP Signal Circuit Open Between Sensor And ECA
MAP/BP Signal Circuit Shorted To VREF, SIG RTN Or Ground
Faulty MAP/BP Sensor
Vacuum Trapped At MAP/BP Sensor
High Atmospheric Pressure
Faulty ECA
VREF Circuit Open At Sensor
SIG RTN Open At Sensor

Turn ignition off. Disconnect MAP/BP sensor from vehicle harness. Connect MAP/BP tester between wiring harness and MAP/BP sensor. Connect "banana plugs" of tester into DVOM, and set DVOM on 20-volt scale.

Turn ignition on. If Red light or no light is on, then VREF is either too high or too low. Go to next step. If Green light is on, VREF is okay. Go to step 3).

2) Check For Power At Sensor Vehicle Harness Connector With MAP/BP sensor and MAP/BP tester connected, turn ignition on. Disconnect MAP/BP sensor. If only Green light on tester is lit, VREF is correct; replace MAP/BP sensor and repeat QUICK TEST. If Green light is not on, remove MAP/BP tester; reconnect MAP/BP sensor and go to TEST C, step 1).

3) Check MAP/BP Sensor Output With MAP/BP tester connected and ignition on, measure sensor output voltage. If output voltage is within range, for altitude in which vehicle is being tested, remove MAP/BP tester and go to next step. If output reading is outside range, remove MAP/BP tester and go to step 5).

Diagnostic Aids - If possible, measure output voltage several known good MAP/BP sensors on available vehicles. The average voltage reading will be typical for your location on date of testing.

MAP SENSOR VOLTAGE OUTPUT

Elevation (Feet)	Volts
0	1.55-1.63
100	1.52-1.60
2000	1.49-1.57
3000	1.46-1.54
4000	1.43-1.51
5000	1.40-1.48
6000	1.37-1.45
7000	1.35-1.43

4) Check Continuity Of MAP/BP SIG Circuit Turn ignition off and wait 10 seconds. Disconnect MAP/BP sensor from vehicle harness. Disconnect ECA 60-pin connector. Inspect for damaged wiring and repair as necessary. Install breakout box, leaving ECA disconnected. Set DVOM on 200-ohm scale. Measure resistance between MAP/BP SIG circuit at sensor vehicle harness connector and test pin No. 45. If reading is less than 5 ohms, replace ECA. Reconnect components and repeat QUICK TEST. If reading is 5 ohms or higher, repair open circuit. Remove breakout box, reconnect components and repeat QUICK TEST.

5) Check MAP/BP SIG Circuit For Shorts To VREF, SIG RTN & Ground Turn ignition off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damaged wiring and repair as necessary. Install breakout box, leaving ECA disconnected. Disconnect harness at MAP/BP sensor. Set DVOM on 200-k/ohm scale. Measure resistance between test pin No. 45 and test pins No. 26, 46, 40 and 60. If any reading is less than 10 k/ohms, repair short circuit. Remove breakout box and reconnect all components. Repeat QUICK TEST. If all readings are 10 k/ohms or more, replace MAP/BP sensor. Remove breakout box and connect all wiring. Repeat QUICK TEST.

NOTE: There is a break in the step numbering sequence at this point, skipping from step 5) to step 7). Break is due to previous chart references to these testing procedures. No test procedures have been omitted.

7) KOER Code 22/126: Check For EGR-Related Codes KOER Code 22/126 indicates MAP/BP signal is out of self-test range during KOER SELF-TEST. Check for Codes 31, 32, 33, 34, 35, 326, 327, 328, 332, 334, 336 or 337. If codes are present, go to appropriate KOER SELF-TEST CODES under SERVICE CODE REFERENCE CHARTS to find the proper CIRCUIT TEST. If codes are not present, go to next step.

8) Check MAP Sensor Operation Turn ignition off and wait 10 seconds. Disconnect vacuum hose from MAP sensor. Connect vacuum pump to MAP sensor and apply 18 in. Hg to sensor. If sensor does not hold vacuum, replace sensor; connect vacuum line and repeat QUICK TEST. If MAP sensor holds vacuum, release vacuum and go to next step.

9) Attempt To Eliminate Code 22/126 Turn ignition off and wait 10 seconds. Plug vacuum hose going to MAP sensor. Start engine and run at 1400-1600 RPM. Slowly apply 15 in. Hg to MAP sensor. With engine operating under these conditions, perform KOER SELF-TEST. Check for Code 22/126; disregard any other codes at this time. If Code 22/126 is still present, replace MAP sensor. If Code 22/126 is no longer displayed, inspect vacuum hose going to MAP sensor. If hose is okay, service other codes at this time. If no other code is present, check engine mechanical condition for cause of low vacuum.

10) Code 72/129: Repeat Dynamic Response (Goose) Test Code 72/129 indicates MAP sensor output did not change enough during dynamic response (Goose) test. Possible causes for this code are as follows:

System failed to detect partial Wide Open Throttle (WOT)
Incorrect MAP sensor vacuum line routing
Faulty MAP sensor

Repeat KOER SELF-TEST. Ensure complete WOT is performed during dynamic response portion of test. If KOER Code 72/129 is still present, go to next step. If code is not present, service other codes as necessary.

11) Code 81/128: Check Vacuum Hoses Continuous memory code 81/128 indicates MAP sensor vacuum has not changed more than 2 in. Hg during normal vehicle operation. Possible causes for this code are as follows:

MAP sensor vacuum supply hose is improperly routed, blocked or is leaking.
MAP sensor is leaking. - With ignition off, check vacuum lines for correct routing. Refer to Vehicle Emission Control Identification (VECI) decal. Check for disconnections, kinks or blockage. Repair vacuum lines as necessary and repeat QUICK TEST. If vacuum lines are okay, go to next step.

12) Check MAP Sensor Operation Turn ignition off and wait 10 seconds. Disconnect vacuum supply hose from MAP sensor. Install vacuum pump to MAP sensor. Apply 18 in. Hg to MAP sensor. If MAP sensor holds vacuum, release vacuum and go to next step. If sensor does not hold vacuum, replace MAP sensor; reconnect components and repeat QUICK TEST.

13) Ensure Vacuum To MAP Sensor Decreases During Dynamic Response (Goose) Test Turn ignition off and wait 10 seconds. Use a "T" fitting to install a vacuum gauge in the intake manifold MAP sensor supply line. Perform KOER SELF-TEST while observing vacuum gauge. If vacuum decreases by more than 10 in. Hg during dynamic response (Goose) test, remove gauge and replace MAP sensor; rerun QUICK TEST. If vacuum does not decrease by 10 in. Hg or more, EEC-IV system is okay; repair engine mechanical components as necessary to increase engine vacuum.

NOTE: There is a break in the step numbering sequence at this point, skipping from step 13) to step 90). Break is due to previous chart references to these testing procedures. No test procedures have been omitted.

90) Continuous Memory Code 22/126: Operate MAP/BP Sensor Continuous Code 22/126 indicates MAP/BP sensor was out of self-test range (1.4-1.6 volts) during normal driving conditions. Possible causes for this code are as follows:

Faulty MAP/BP Sensor
Faulty wiring harness or connectors
Unusually high or low barometric pressure

While in KOEO wiggle test (see CONTINUOUS MONITOR MODE (WIGGLE TEST) under QUICK TEST), observe test equipment while performing the following:

Connect a vacuum pump to MAP/BP sensor.
Slowly apply 25 in. Hg to sensor.
Slowly bleed off vacuum from sensor.
Lightly tap on sensor (to simulate road shock).
Wiggle sensor connector.

If a fault is indicated, disconnect sensor and inspect connectors. Repair as necessary. If connectors are okay, replace MAP/BP sensor. Rerun QUICK TEST. If a fault is not indicated, go to next step.

91) Check EEC-IV Vehicle Harness Stay in KOEO wiggle test. Observe VOM or diagnostic tester for indication of fault while shaking, bending or wiggling small sections of harness from sensor connector to firewall. Check harness from firewall to ECA in same manner. If fault is indicated, isolate fault in harness and repair as necessary. Clear codes and repeat QUICK TEST. If no fault is indicated, go to next step.

92) Check ECA & Vehicle Harness Connectors Turn ignition off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect both connectors and terminals for obvious damage. If connectors and terminals are not okay, repair as necessary. Repeat QUICK TEST. If connectors and terminals are okay, fault cannot be duplicated at this time. Continuous Memory Code 22/126 testing is complete. Refer to INTERMITTENTS in the TESTS W/O CODES article.