Normal Operation
WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The voltage required for correct Electronic Power Assist Steering (EPAS) system operation is 11-16 volts. Above or below that voltage range, DTC B1317 (battery voltage high) or DTC B1318 (battery voltage low) will be set.
Fused ignition voltage for the EPAS system is supplied to the control module by Smart Junction Box (SJB) fuse 35 (10A) along circuit CBP35 (YE/GY). Fused battery voltage for the power steering motor is supplied to the Power Steering Control Module (PSCM) by Battery Junction Box (BJB) 80A MIDI (WH) fuse along circuit SBB01 (RD). Ground for the PSCM is provided along circuit GD116 (BK/VT).
- DTC B1317 (Battery Voltage High) - When the battery or charging system voltage exceeds 16 volts for more than 1,000 ms, DTC B1317 will be set.
- DTC B1318 (Battery Voltage Low) - When the battery or charging system voltage drops below 9 volts for more than 4,000 ms, DTC B1318 will be set.
- These DTCs may also result in a reduced amount of steering assist.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Charging system
- PSCM