Vehicle: 2007 Dodge Caravan, V6-3.3L, VIN R
Problem: This vehicle came to the shop because
the engine would crank but not start and the MIL was on. The
camshaft (CMP) and crankshaft (CKP) sensors had already been
replaced but did not fix the problem.
Details: The technician connected a scan tool
and pulled DTCs P0335 (CKP sensor circuit signal) and P0340 (CMP
sensor circuit signal). The Tech-Assist consultant advised the
technician to scope-test the CKP signal wire. There was no
signal. Next, the technician checked the Pink/Yellow (Circuit
F855) wire for a 5-volt reference voltage at the CKP and CMP.
There was only 1-volt at both sensors.
After reviewing the wiring diagram, the Tech-Assist consultant
noted that the MAP (Manifold Absolute Pressure) sensor, the TPS
(Throttle Positon Sensor), CMP, CKP, AC Pressure sensor and the
EGR (Exhaust Gas Recirculation) valve were all on the same
circuit. He asked the technician to unplug each sensor one at a
time while monitoring the reference signal at the CKP sensor
Confirmed Repair: When the technician unplugged
the EGR valve, the 5-volt reference returned to all of the
sensors on the circuit. He replaced the EGR valve, cleared the
DTCs and the engine started. The problem was fixed.