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Pinpoint Test E: Pats Transceiver Module Signal Is Not Received

E1 RETRIEVE THE DTCS
- Clear the continuous DTCs.
- Key in OFF position.
- Key in ON position.
- Retrieve the PCM continuous DTCs.
- Is DTC B1681 retrieved?
- Yes : GO to E2.
- No : The system is OK.

E2 CHECK THE PATS TRANSCEIVER CIRCUIT 296 (WH/VT) FOR VOLTAGE
- Key in OFF position.
- Disconnect: PATS transceiver C2007.
- Key in ON position.
- Measure the voltage between the PATS transceiver C2007-1, circuit 296 (WH/VT), harness side and ground.
- Is the voltage greater than 10 volts?
- Yes : GO to E3.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

E3 CHECK THE PATS TRANSCEIVER GROUND CIRCUIT 570 (BK/WH) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the PATS transceiver C2007-2, circuit 570 (BK/WH), harness side and ground.
- Is the resistance less than 5 ohms?
- Yes : GO to E4.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

E4 CHECK THE PATS TRANSCEIVER RECEIVE CIRCUIT 167 (BN/OG) FOR VOLTAGE
- Connect: PATS transceiver C2007.
- Key in ON position.
- Measure the voltage by back-probing between the PATS transceiver C2007-3, circuit 167 (BN/OG), harness side and ground.
- Is the voltage greater than 9 volts?
- Yes : GO to E6.
- No : GO to E5.

E5 CHECK THE PATS TRANSCEIVER RECEIVE CIRCUIT 167 (BN/OG) FOR A SHORT TO GROUND
- Key in OFF position.
- Disconnect: PATS transceiver C2007.
- Measure the resistance between the PATS transceiver C2007-3, circuit 167 (BN/OG), harness side and ground.
- Is the resistance greater than 10,000 ohms?
- Yes : GO to E6.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. If the system fails again, INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS - 2.3L or ELECTRONIC ENGINE CONTROLS - 3.0L (4V) .

E6 CHECK CIRCUIT 167 (BN/OG) FOR AN OPEN
- Key in OFF position.
- Disconnect: PCM C175b.
- Measure the resistance between the PATS transceiver C2007-3, circuit 167 (BN/OG), harness side and PCM C175b-31, circuit 167 (BN/OG), harness side.
- Is the resistance less than 5 ohms?
- Yes : GO to E7.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

E7 CHECK THE PATS TRANSCEIVER TRANSMIT CIRCUIT 168 (RD/BK) FOR VOLTAGE
- Connect: PATS transceiver C2007.
- Connect: PCM C175b.
- Key in ON position.
- Measure the voltage by back-probing between the PATS transceiver C2007-4, circuit 168 (RD/BK), harness side and ground.
- Is the voltage greater than 9 volts?
- Yes : GO to E11.
- No : GO to E8.

E8 CHECK THE PATS TRANSCEIVER TRANSMIT CIRCUIT FOR A SHORT TO GROUND CIRCUIT 168 (RD/BK) TRANSCEIVER CONNECTED
- Key in OFF position.
- Disconnect: PCM C175b.
- Measure the resistance between the PCM C175b-42, circuit 168 (RD/BK), harness side and ground.
- Is the resistance greater than 10,000 ohms?
- Yes : GO to E10.
- No : GO to E9.

E9 CHECK THE PATS TRANSCEIVER TRANSMIT CIRCUIT FOR A SHORT TO GROUND CIRCUIT 168 (RD/BK) TRANSCEIVER DISCONNECTED
- Disconnect: PATS transceiver C2007.
- Measure the resistance between the PATS transceiver C2007-4, circuit 168 (RD/BK), harness side and ground.
- Is the resistance greater than 10,000 ohms?
- Yes : INSTALL a new PATS transceiver. REFER to PASSIVE ANTI-THEFT SYSTEM (PATS) TRANSCEIVER . CLEAR the DTCs. REPEAT the self-test.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

E10 CHECK THE PATS TRANSMIT CIRCUIT 168 (RD/BK) FOR AN OPEN
NOTE: When a new PCM is installed, the encoded ignition keys must be reprogrammed.
- Disconnect: PATS transceiver C2007.
- Measure the resistance between the PATS transceiver C2007-4, circuit 168 (RD/BK), harness side and the PCM C175b-42, circuit 168 (RD/BK), harness side.
  
  Fig 9: Measuring Resistance Between Pats Transceiver C2007-4 Circuit 168 (RD/BK), Harness Side And The PCM C175b-42, Circuit 168 (RD/BK), Harness Side
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to E13.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

E11 CHECK THE TRANSCEIVER TRANSMIT CIRCUIT 168 (RD/BK) FOR VOLTAGE
- Select PCM active command TRANSMIT SIGNAL COMMAND.
- Trigger TRANSMIT to ON.
- Measure the voltage by back-probing between the PATS transceiver C2007-4, circuit 168 (RD/BK), harness side and ground.
- Is the voltage less than 5 volts?
- Yes : INSTALL a new PATS transceiver. REFER to PASSIVE ANTI-THEFT SYSTEM (PATS) TRANSCEIVER . CLEAR the DTCs. REPEAT the self-test.
- No : GO to E12.

E12 CHECK CIRCUIT 168 (RD/BK) FOR A SHORT TO BATTERY
NOTE: When a new PCM is installed, the encoded ignition keys must be reprogrammed.
- Key in OFF position.
- Disconnect: PCM C175b.
- Disconnect: PATS transceiver C2007.
- Key in ON position.
- Measure the voltage between the PATS transceiver C2007-4, circuit 168 (RD/BK), harness side and ground.
- Is any voltage present?
- Yes : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
- No : GO to E13.

E13 CHECK THE PCM FOR CORRECT OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS - 2.3L or ELECTRONIC ENGINE CONTROLS - 3.0L (4V) . REPROGRAM the encoded ignition keys. REFER to KEY PROGRAMMING USING DIAGNOSTIC EQUIPMENT . CLEAR the DTCs. REPEAT the self-test.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.