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Diagnostic Flow Chart

Special Tools

Illustration	Tool Name	Tool Number
Courtesy of FORD MOTOR CO.	Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool.

Prior to carrying out the flow test, the following items should be checked:

Know and understand the customer concerns.
Check the transmission fluid level and condition.
Verify the concern by operating the vehicle.
Check for non-factory-installed items and verify correct installation.
Check the selector lever linkage adjustments.
Check TSB messages for vehicle concerns.
Carry out both Key ON Engine OFF (KOEO) and Key ON Engine Running (KOER) self-test.
Record all DTCs.

DIAGNOSTIC FLOW CHART

Test	Result	Action
1) Were any DTCs recorded?	Yes	REPAIR all hard DTCs. FOLLOW the pinpoint tests. REFER to the Introduction - Gasoline Engines article first, then this article, then Go to Step 2.
	No	REFER to Diagnosis By Symptom ., then Go to Step 5.
2) Are any continuous test memory codes present?	Yes	CLEAR codes and CARRY OUT drive cycle test, then Go to Step 3.
	No	Go to Step 4.
3) Did the continuous test memory codes reappear?	Yes	REPAIR all continuous test memory codes. FOLLOW the pinpoint tests. REFER to the Introduction - Gasoline Engines article then the transmission reference information, then this article, then Go to Step 4.
	No	Go to Step 4.
4) Is the concern repaired?	Yes	CARRY OUT the Key ON Engine OFF (KOEO) and Key ON Engine Running (KOER) self test to verify that no DTCs are present. CLEAR memory codes.
	No	REFER to Diagnosis By Symptom , then Go to Step 5.
5) Are there any electrical concerns?	Yes	INSTALL the scan tool. CARRY OUT KOEO and KOER tests and drive cycle test with the scan tool, then Go to Step 6.
	No	REFER to the hydraulic and mechanical routine to diagnose and repair the concern, then Go to Step 7.
6) Was the transmission concern corrected when the scan tool was installed?	Yes	REFER to the Introduction - Gasoline Engines article, intermittent fault diagnosis article and use the scan tool to diagnose cause of concern in the processor, vehicle harness or external inputs (sensors or switches).
	No	REFER to the hydraulic and mechanical routine to diagnose the concern, then Go to Step 7.
7) Is the concern repaired?	Yes	CARRY OUT the final quick test to verify that no DTCs are present. CLEAR memory codes.
	No	Concern should have been repaired. GO back through the Diagnostic Flow Chart and review other components that may have contributed to the concern. CHECK and DIAGNOSE those components. Get assistance from other sources.