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Timothy provides a useful video for pulling an error code on a fuel-injected Festiva here.
I searched for but didn't find a related thread concerning electronic fuel control system diagnostics on carbureted Festivas. Since the procedure to pull fault codes on these cars is different, the following instruction is provided. It is taken from the OEM 1988 shop manual, pp. 29-01C-7 to 29-01C-9.
Required materials:
Analog voltmeter
Pen & paper to record fault code conversion(s)
Method:
1. Ground the 1-pin service (test) connector. The test coupler is in the right rear corner of the engine bay as you look from the front of the car. It will hang out of the harness next to the multi-pin self-test connector for the Rotunda Star tester. Reference connector B-14 if you have a schematic.
2. Connect the voltmeter between the green/red terminal under the dash on the six-pin self test connector (B-16) and ground.
3. Read the voltmeter pulses (i.e., sweeps of the needle). The pulses are converted as follows:
a. Long pulse = 10
b. Short pulse = 01
Example: 1 long pulse + 5 short pulses = code 15.
It is not noted in the manual that the foregoing procedure requires the ignition key to be in the On position. Only when using the Ford Rotunda "Super Star" electronic tester is this necessary. That said, I'd keep my key handy in the event that it's needed when using the voltmeter method.
Per Chart D on p. 29-01C-7, 18 non-sequential codes are programmed in the system. I've reproduced them below. The shop manual provides considerable written and graphic detail to address any fault code(s) obtained using the voltmeter.
01 - Ignition coil
09 - Engine coolant temperature sensor
13 - MAP sensor
15 - EGO sensor
16 - EGR valve position sensor
17 - Feedback system
18 - ABC valve #1
19 - ABC valve #2
20 - ABC valve #3
21 - ABC valve #4
22 - Slow fuel cut solenoid
28 - No. 1 EGR solenoid vacuum valve
29 - No. 2 EGR solenoid vacuum valve
31 - ACV solenoid valve
34 - E/L solenoid valve
35 - A/C solenoid valve
38 - PTC heater relay
70 - Vacuum switch
-SH
I searched for but didn't find a related thread concerning electronic fuel control system diagnostics on carbureted Festivas. Since the procedure to pull fault codes on these cars is different, the following instruction is provided. It is taken from the OEM 1988 shop manual, pp. 29-01C-7 to 29-01C-9.
Required materials:
Analog voltmeter
Pen & paper to record fault code conversion(s)
Method:
1. Ground the 1-pin service (test) connector. The test coupler is in the right rear corner of the engine bay as you look from the front of the car. It will hang out of the harness next to the multi-pin self-test connector for the Rotunda Star tester. Reference connector B-14 if you have a schematic.
2. Connect the voltmeter between the green/red terminal under the dash on the six-pin self test connector (B-16) and ground.
3. Read the voltmeter pulses (i.e., sweeps of the needle). The pulses are converted as follows:
a. Long pulse = 10
b. Short pulse = 01
Example: 1 long pulse + 5 short pulses = code 15.
It is not noted in the manual that the foregoing procedure requires the ignition key to be in the On position. Only when using the Ford Rotunda "Super Star" electronic tester is this necessary. That said, I'd keep my key handy in the event that it's needed when using the voltmeter method.
Per Chart D on p. 29-01C-7, 18 non-sequential codes are programmed in the system. I've reproduced them below. The shop manual provides considerable written and graphic detail to address any fault code(s) obtained using the voltmeter.
01 - Ignition coil
09 - Engine coolant temperature sensor
13 - MAP sensor
15 - EGO sensor
16 - EGR valve position sensor
17 - Feedback system
18 - ABC valve #1
19 - ABC valve #2
20 - ABC valve #3
21 - ABC valve #4
22 - Slow fuel cut solenoid
28 - No. 1 EGR solenoid vacuum valve
29 - No. 2 EGR solenoid vacuum valve
31 - ACV solenoid valve
34 - E/L solenoid valve
35 - A/C solenoid valve
38 - PTC heater relay
70 - Vacuum switch
-SH