B1222: Fuel Temperature #1 Circuit Failure

DTC B1222 - Fuel Temperature Sensor No. 1 Circuit Failure

NOTE: Ford DOES NOT provide a procedure to perform the following pinpoint test without the Rotunda New Generation Star (NGS) tester 007-00500 or Rotunda Breakout Box 014-00322, or equivalent equipment.

B1222-1 - Check Fuel Temperature Sensor No.1 Operation

- Disconnect fuel indication module connector.
- Install Rotunda Breakout Box 014-00322 or equivalent between fuel indication module and harness.
- Turn ignition switch to RUN.
- Using a voltmeter, measure the voltage between breakout box pin 47 and 46.

Is voltage greater than 4.55 volts?

YES GO to B1222-2.
NO GO to B1222-5.

B1222-2 - Check Sensor Output

- Turn ignition switch to OFF.
- Disconnect tank temperature sensor No.1.
- Connect a jumper wire between circuit 875 (BK/LB) and 925 (W/Y) at the sensor connector.
- Turn ignition switch to RUN.
- Using a voltmeter, measure the voltage between breakout box pin 47 and pin 46.

Is voltage now less than 0.12 volt?

YES REPLACE fuel temperature sensor No. 1. RESTORE vehicle. RETEST system.
NO GO to B1222-3.

B1222-3 - Check Circuit 875 (BK/LB)

- Turn ignition switch OFF.
- Disconnect fuel indication module, leave breakout box connected to harness.

Fuel Tank Temperature Sensor No. 1 Connector:

- Using an ohmmeter, measure the resistance of circuit 875 (BK/LB) between breakout box pin 46 and circuit 875 (BK/LB) at sensor connector.

Is resistance 5 ohms or less?

YES GO to B1222-4.
NO SERVICE circuit 875 (BK/LB) for open. RESTORE vehicle. RETEST system.

B1222-4 - Check Circuit 875 (BK/LB) For Short To B+

- Turn ignition switch to OFF.
- Using a voltmeter, measure for voltage between breakout box pin 46 and 40 or 60.

Is voltage less than 0.5 volt?

YES GO to B1222-5.
NO SERVICE circuit 875 (BK/LB) for short to B+. RESTORE vehicle. RETEST system.

B1222-5 - Check For Shorted Fuel Temperature Sensor

- Turn ignition switch to OFF.
- Disconnect fuel temperature sensor No. 1.
- Turn ignition switch to RUN.
- Using a voltmeter, measure for voltage between breakout box pins 47 and 46.

Is voltage greater than 4.55 volts?

YES REPLACE fuel temperature sensor No. 1. RESTORE vehicle. RETEST system.
NO GO to B1222-6.

B1222-6 - Check Circuit 875 (BK/LB) For Short To Ground

- Turn ignition switch to OFF.
- Disconnect fuel indication module from breakout box, leave breakout box connected to harness.
- Using an ohmmeter, measure the resistance between breakout box pin 40 and 46.

Is resistance greater than 10K ohms?

YES G0 to B1222-7.
NO SERVICE circuit 875 (BK/LB) for short to ground. RESTORE vehicle. RETEST system.

B1222-7 - Check For Erratic Voltage On Circuit 925 (W/Y)

CAUTION: The voltmeter function of the New Generation Star (NGS) Tester will be used to monitor and record voltages in this test step. Do not affempt to use a standard voltmeter to perform this test or inaccurate readings will be received possibly leading to inaccurate repairs.

- Connect fuel indication module to breakout box and harness connector assembly.
- Connect fuel temperature sensor No.1 connector.
- Start engine.
- Connect positive lead to breakout box pin 47.
- Connect negative lead to breakout box pin 40 or 60.
- Select VOLTMETER.
- Select LINK.
- Select PI/DATA.
- Select FIM.
- Select TEMPS2.
- Select START.
- Select REC.
- Push TRIGGER to capture data.
- Push TRIGGER to store data.
- Select VIEW to examine data.

Does voltage vary rapidly over a range of 0.2 to 4.9 volts?

YES SERVICE harness or connectors for intermittent connection. RESTORE vehicle. RETEST system.
NO REPLACE fuel indication module. RESTORE vehicle. RETEST system.