Bcp Pin-Point Diagnostics (Ecm To Bcp Sensor- Valve Cover Removed) - Navistar International DT 466 Diagnostic/Troubleshooting Manual

7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS
BCP Pin-Point Diagnostics (ECM to BCP Sensor–
valve cover removed)
Figure 395 BCP circuit diagram with UVC Pressure Sensor Breakout Harness
Operational Voltage Checks for BCP Sensor with UVC Pressure Sensor Breakout Harness (Check
with UVC Pressure Sensor Breakout Harness connected to UVC connector and sensor.)
NOTE: These checks are done only if an EST is not available. Do not use this method to measure BCP when
engine is running.
Test Point EST voltage readings:
Signal to ground
3 to 1 0.15 V to 0.3 V
3 to 1 0.15 V to 0.3 V
BCP Diagnostic Trouble Codes
DTC 126 = Signal voltage was < 0.039 V for more than 0.1 second
DTC 127 = Signal voltage was > 4.9 V for more than 0.1 second
DTC 546 = Brake control pressure was < 4 MPa (580 psi) for more than 3.0 seconds
DTC 547 = Brake control pressure was > 4.5 MPa (653 psi) for more than 3.0 seconds
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Spec
0 kPa (0 psi)
0 kPa (0 psi)
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
Checks
Atmospheric pressure with key-on
engine-off
Maximum at engine cranking speed
333