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Home >> Ford >> 1990 >> Bronco II RWD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Quick Test >> Step 7.0 KOER Code-To-Test Chart
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Step 7.0 KOER Code-To-Test Chart

Starting with the lowest Engine Running code, use the chart to locate the proper pinpoint test for the applicable engine. All tests are in the format "Test/Step". For example, if you see "H23", proceed to pinpoint test H (TEST H - FUEL CONTROL) and start at step #23. Be sure to read the Introduction proceeding step #1 for important supplementary information and resources.

The chart is hyperlinked for your convenience. Each link jumps to the start of the test (introduction area) proceeding step #1, not to the specified step number itself.

Since just one hyperlink can exist on a line, only the left-most pinpoint test identifier is linked. If another engine uses the same test but is not linked, use the same left-most hyperlink.

After service, rerun the Quick Test to ensure that service was effective.

To find out the meaning of any code, see the CODE DEFINITION TABLES .

ENGINE RUNNING (KOER) CODE-TO-TEST CHART: TRUCK (1)

KOEO Eng. Run.Code 2.3LVIN [A] 2.9LVIN [T] Fed. 2.9LVIN [T] Cal. 3.0LVIN [U] 4.0LVIN [X] 4.9LVIN [Y] 5.0LVIN [N] (2) 5.8LVIN [H] 7.3LVIN [M] 7.5LVIN [G]
12 KE1 KE1 KE1 KE1 KE1 KE1 KE1 KE1 -- KE1
13 KE15 KE15 KE15 KE15 KE15 KE15 KE15 KE15 -- KE15
16 KE1 -- -- -- -- -- -- -- -- --
18 P1 -- P1 -- -- P1 P1 P1 -- P1
21 DA1 DA1 DA1 DA1 DA1 DA1 DA1 DA1 -- DA1
22 DF7 DF7 DF7 DF7 DF7 DF7 DF7 DF7 DF7 DF7
23 DH1 DH1 DH1 DH1 DH1 DH1 DH1 DH1 DQ1 DH1
24 DA1 DA1 DA1 DA1 DA1 DA1 DA1 DA1 -- DA1
25 -- DG1 -- -- -- DG1 DG1 -- -- --
26 DC1 -- DC1 -- DC1 TC30 -- TC30 TC30 TC30 TC30
31 DN1 -- -- -- -- DN1 DN1 DN1 -- DN1
32 DN25 -- -- -- -- DN25 DN25 DN25 -- DN25
33 DN40 -- -- -- -- DN40 DN40 DN40 -- DN40
34 DN50 -- -- -- -- DN50 DN50 DN50 -- DN50
35 DN5 -- -- -- -- DN5 DN5 DN5 -- DN5
41 H11 H11 H11 H11 H11 H11 H11 H11 -- H11
42 H23 H23 H23 H23 H23 H23 H23 H23 -- H23
44 -- -- -- -- -- KC1 KC1 KC1 -- KC1
45 -- -- -- -- -- KC1 KC1 KC1 -- KC1
46 -- -- -- -- -- KC1 KC1 KC1 -- --
52 FF5 -- -- FF5 -- FF5 FF5 -- -- --
56 DC20 -- DC20 -- DC20 -- -- -- -- --
65 -- -- -- -- -- TC10 TC10 TC10 TC10 TC10
66 DC10 -- DC10 -- DC10 -- -- -- -- --
72 DF10 DF10 DF10 DF10 DF10 DF10 DF10 DF10 -- DF10
73 DH20 DH20 DH20 DH20 DH20 DH20 DH20 DH20 -- DH20
74 FD10 FD10 FD10 FD10 FD10 FD10 -- FD10 FD10 FD10
77 M1 M1 M1 M1 M1 M1 M1 M1 -- M1
98 STEP 3.0: PERFORM KOEO SELF-TEST
(1) If no codes or codes not listed, go to test QA1. "--" means code does not apply for this engine. "Fed." means Federal, "Cal." means California.
(2) 5.0L information has been updated to reflect Ford TSB 89-25A-14.