For vehicles made after 1996, retrieving the codes of the check engine light in your dash panel is simple. All you need to do is find your diagnostic connector located under the dash by the driver side. You can then hook up a scanner and the codes will be displayed for you. If you don't have any scanner like most drivers, you can bring your vehicle to any local automotive store and they will usually scan the codes FREE for you. However, for vehicles made on or before 1995, there is only one cheap way to get it: You do it yourself!

On board diagnostic (OBD) was designed on vehicles equipped with electronic fuel injection so you can generally retrieve the codes yourself. No need buying a scanner or running to any parts stores to check the engine light.
This system is called obd1 and applies to most vehicles made before 1995 for domestics and 1993 on imports.

Before you start the engine should be warmed up completely, in park with the air conditioner in the off position. A test light is used as the flash indicator that will identify the two digit code number. Once a grounded test light is connected to the data port connector turn the key to the "on" position without starting the engine. The test light will begin to flash on then off, count the flashes, when the flashing stops the first digit is complete, then the system will pause and the second digit will begin flashing. For example the test light flashes twice and then pauses and flashes six more times the code number is 26.

If the system flashes eleven there are no codes to report. To clear system codes simply remove the negative battery cable for thirty seconds and reconnect. The data link connector is usually under the hood near the battery.




Below are the OBD DTC's for 1995-previous model year EFI-equipped Ford vehicles.

11 system pass
12 idle control fault
13 dc motor did not move
14 engine rpm signal fault or PIP circuit failure
15 eec processor or power to KAM interrupted
16 rpm to low to check oxygen sensor test or fuel control error
17 cfi fuel control system fault or rich/lean condition indicated
18 ignition diagnostic monitor (IDM) circuit failure
19 cylinder identification (CID) sensor input failure
21 engine coolant temperature (ECT) out of self-test range
22 manifold absolute pressure (MAP) sensor circuit out of range
23 throttle position sensor out of self-test range
24 air charge temperature (ACT) sensor out of self-test range
25 knock not sensed during dynamic response test
26 transmission fluid temperature out of self-test range
28 loss of primary tach, right side
29 insufficient input from vehicle speed sensor
31 egr position sensor below minimum voltage
32 egr position sensor below closed limit
33 throttle position sensor noisy/harsh on line
34 egr valve circuit out of self-test range
35 egr valve circuit above maximum voltage
38 idle track switch circuit open
39 axod torque converter or bypass clutch not applying properly
41 oxygen sensor circuit indicates system always lean
42 oxygen sensor circuit indicates system always rich
43 oxygen sensor out of self-test range
44 air injection control system failure
45 coil 1 primary circuit failure
46 coil primary circuit failure
47 4X4 switch is closed or oxygen sensor failure
48 coil primary circuit failure
49 electronic transmission shift error
51 engine coolant temperature sensor circuit open
52 power steering pressure switch circuit open
53 throttle position circuit above maximum voltage
54 air charge temperature circuit open
55 key power input to processor open circuit
56 mass air flow circuit above maximum voltage
57 axod circuit failure
58 idle tracking switch circuit fault
59 automatic transmission shift error
61 engine coolant temperature circuit grounded
62 converter clutch error
63 throttle position circuit below minimum voltage
64 air charge temperature circuit grounded
65 charging system over voltage
66 mass air flow sensor circuit below minimum voltage
67 neutral/drive switch circuit open
68 transmission fluid temperature over temperature transmission shift error
70 data circuit communication link circuit failure
71 message center circuit circuit failure
72 insufficient manifold absolute pressure (MAP) change during dynamic response test
73 insufficient throttle position (TPS) change during dynamic response test
74 brake on/off (BOO) circuit open
75 brake on/off (BOO) circuit closed
76 insufficient air flow output change during test
77 brief wide open throttle not sensed during test
78 power interrupt detected
79 a/c on/defrost on during self test
81 map has not changed normally
82 super charger bypass circuit failure
83 OIC-low speed fuel pump relay circuit failure
84 egr vacuum regulator (EVR) circuit failure
85 canister purge circuit failure
86 shift solenoid circuit failure
87 fuel pump circuit failure
88 electro drive fan circuit failure
89 transmission solenoid circuit failure
91 no oxygen sensor switching detected
92 shift solenoid circuit failure
93 throttle position sensor input low
94 torque converter clutch solenoid circuit failure
95 fuel pump secondary circuit failure
96 fuel pump secondary circuit failure
97 transmission indicator circuit failure
98 electronic pressure control circuit failure
99 eec has not learned to control idle