Page 1 of 6 Your Current Vehicle: 2005 Ford Thunderbird Front Electronic Module (FEM) SECTION 419-10: Multifunction Electronic Modules 2005 Thunderbird Workshop Manual DIAGNOSIS AND TESTING Procedure revision date: 06/25/2004 Front Electronic Module (FEM) Special Tool(s) 73III Automotive Meter 105-R0057 or equivalent Worldwide Diagnostic System (WDS) Vehicle Communication Module (VCM) with appropriate adapters, or equivalent diagnostic tool Inspection and Verification 1. Verify the customer concern. 2. Visually inspect for obvious signs of electrical damage. Visual Inspection Chart
Page 2 of 6 Electrical Central junction box (CJB) fuses: 20 (10A) 30 (5A) Wiring harness Connector(s) Circuitry 3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step. 4. If the cause is not visually evident, connect the diagnostic tool to the data link connector (DLC) and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle: check that the program card is correctly installed. check the connections to the vehicle. check the ignition switch position. 5. If diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual. 6. Carry out the data link diagnostics test. If the diagnostic tool responds with: SCP or UBP circuits fault; all electronic control units no response/not equipped, refer to Module Communications Network. No response/not equipped for FEM, Go To Pinpoint Test A. System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out self-test diagnostics for the DSM. 7. If the DTCs retrieved are related to the concern, go to the Diagnostic Trouble Code (DTC) Index to continue diagnosis. 8. If no DTCs related to the concern are retrieved, GO to Symptom Chart. Symptom Chart Symptom Chart
Page 3 of 6 Condition Possible Sources Action DLC Circuit 29-DK20 (OG/GN) Circuit 29S-DK21 (OG/WH) Circuit 31-DK20 No communication with the front electronic module (FEM) Circuit 31-DK20A Circuit 31-DK20B Circuit 31-DK20C Circuit 31-DK20D Diagnostic tool FEM C201a, C201c FEM Go To Pinpoint Test A. Connector Circuit Reference Front Electronic Module (FEM) C201a Click to Enlarge Pin Number(s) 1 Circuit Designation/Description 29S-DK21 (OG/WH) FEM power supply. Normal Condition/Measurement 10 volts or greater at the FEM connector.
Page 4 of 6 Pin Circuit Number(s) Designation/Description 11 31-DK20A FEM ground. 13 31-DK20B FEM ground. 14 31-DK20C FEM ground. 15 31-DK20D FEM ground. Front Electronic Module (FEM) C201c Normal Condition/Measurement Click to Enlarge Pin Circuit Normal Condition/Measurement Number(s) Designation/Description 29-DK20 (OG/GN) FEM power 6 10 volts or greater at the FEM connector. supply. 12 31-DK20 FEM ground. Pinpoint Test A: No Communication With The Front Electronic Module (FEM) Refer to Wiring Diagrams Cell 14 for schematic and connector information. Normal Operation The FEM controls the RH exterior mirrors, the power adjustable pedals, both interior and exterior lighting active anti-theft functions, and the brake shift interlock. Power is supplied through the central junction box (CJB) fuse 20 (10A) and fuse 30 (5A) on circuits 29-DK20 (OG/GN), 29S-DK21 (OG/WH) and grounded through circuit 31-DK20, 31-DK20A, 31-DK20B, 31-DK20C, and 31-DK20D. Possible Causes circuit 29-DK20 (OG/GN) open or short to ground circuit 29S-DK21 (OG/WH) open or short to ground circuit 31-DK20 open circuit 31-DK20A open
Page 5 of 6 circuit 31-DK20B open circuit 31-DK20C open circuit 31-DK20D open FEM PINPOINT TEST A: NO COMMUNICATION WITH THE FRONT ELECTRONIC MODULE (FEM) Test Step Result / Action to Take A1 CHECK CIRCUITS 29-DK20 (OG/GN) AND 29S-DK21 (OG/WH) FOR VOLTAGE Ignition OFF. Disconnect: FEM C201a. Disconnect: FEM C201c. Ignition ON. Measure the voltage between the FEM C201a-1, circuit 29S-DK21 (OG/WH), harness side and ground; and between the FEM C201c-6, circuit 29-DK20 (OG/GN), harness side and ground. Yes GO to A2. No REPAIR the circuit in question. TEST the system for normal operation. Are the voltages greater than 10 volts? A2 CHECK THE FEM GROUND CIRCUITS FOR AN OPEN
Page 6 of 6 Test Step Ignition OFF. Result / Action to Take Use the following table to measure the resistance between the FEM connector, harness side and ground: Connector-Pin Circuit C201a-11 31-DK20A C201a-13 31-DK20B C201a-14 31-DK20C C201a-15 31-DK20D C201c-12 31-DK20 Yes REFER to Module Communications Network. No REPAIR the circuit in question. TEST the system for normal operation. Are the resistances less than 5 ohms? Copyright 2016 by Chilton, an imprint of Cengage Learning (/lh/home/index/mwellpbnfaynj2njlplf8lnciuznjevlgpul8nacaljnp9mg1)home Terms and Conditions (http://www.cengage.com/content/footer/terms_of_use.aspx) Privacy Statement (http://www.cengage.com/content/footer/privacy_statement.aspx) Contact Us(http://www.cengage.com/contact/)