Basic Diagnostic Procedure

1. Verify the customer's complaint under similar conditions as described by the customer. (Road test with customer if possible.)

2. During road test note what is correct and what is not; i.e. shift points, shift feel, manual gear selection, engine braking, noises, etc. Record findings on the Hydraulic-Mechanical Checklist for later reference.

3. Refer to Automatic Transmission Troubleshooting Chart and Fault Finding Tables found in Group 24 of the Repair Manuals for recommended checks based on findings in step 2.

4. Perform necessary checks and determine type of repair needed, referring to the attached Diagnostic Hints and Fault Finding Tables found in Group 24 of the Repair Manuals.

Do not overlook the 2013 Diagnostic Module as an important tool in the diagnostic procedure. Performing a "Brief Test" may quickly turn up faults not only in the EGS system on EH version transmissions, but also in other vehicle systems which may affect transmission operation irregardless of H or EH version. On EH versions, if no faults are found and diagnosis is not possible at this point, further interrogation of the electronic control system should be conducted via the 2013 Diagnostic Module and EGS pin by pin testing as necessary to further pinpoint the failure mode before replacing any parts.