Camshaft Position Sensor/Electrical Problems | Ford Explorer Forums - Serious Explorations

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John LaClair

New Member
January 17, 2019
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City, State
Paw Paw
Year, Model & Trim Level
03 Explorer Cen. 4.6L 4x4
As stated in a previous post, I have multiple codes on my 2003 Ford Explorer Centennial Edition, 4.6L. After testing my alternator I figured most of them were due to it being weak. After removing countless alternators at the junkyard and testing them outside of the vehicle, I finally found one that passed. Installed it, didn't fix the issue. Out of curiosity I tested the original alternator and found that one also passed the test outside of the vehicle. So I checked the voltage at the battery with the engine running again and it was 13.6V. I thought maybe the fusible link was the issue, so I tested the voltage at the post on the alternator itself, which also read 13.6V. After this, I tested the voltage coming into the alternator at the plug, and that was also reading about 13.6V. Voltage at the camshaft position sensor is reading 0.6V, which evidently is way below what it should be, but both the camshaft position sensor and the pigtail have been replaced recently.

I'm a little stumped by this. Does this mean there is something wrong in the wiring between the PCM and the alternator? Another sensor somewhere? A blown or corroded fuse? A problem with the PCM itself? Could the low alternator output be causing the P0340, U1059, U1262, and park assist module codes? How do I go about testing this?

Also, if you have an idea what might be the causes of these codes feel free to comment. Any input on any of it potentially makes my job easier and is greatly appreciated. On a side note, the Explorer was t-boned when owned by the previous owner. There is no frame damage, just caved in some body panels on that side, but could there be a damaged wiring harness or EVAP line on that side causing some of these problems?

Thank you for any and all help!!!!!!!!!!!!!

The codes are as follows:
P0340 - CMP Circuit Fault
P0420 - Catalyst System Efficiency Below Threshold
P0442 - EVAP System Leak Detected
U1059 - Transmission Position Data Invalid
U1262 - SCP Data Link Fault

Parking aid codes:
C1710 - Rear Inner Right Sensor Fault
C1709 - Rear Inner Right Sensor Circuit Failure
C1706 - Rear Inner Left Sensor Circuit Failure
C1704 - Rear Outer Right Sensor Fault
C1701 - Rear Outer Left Sensor Fault