Hey Scotty/Community!
To the point:
2003 Nissan Pathfinder
3.5L V6 4x4
No CEL, but showing Trouble code P0550-Power steering pressure sensor when using scan tool.
Truck is in limp mode. Changed out the sensor but it’s still tripping the code and the truck is still in limp mode.
A reputable transmission mechanic on another forum assisted with wiring diagrams, etc for me to trouble shoot. Tried everything he referenced and truck is still in limp mode.
Mechanic thinks it’s a bad ground causing the diagnosis. Cleaned all of the grounds I could locate.
What suggestions do you have to troubleshoot before I throw in the towel and send to the mechanic! I understand that the replacement sensor could be faulty. It is supposed to be an OEM replacement, not aftermarket.
Thanks!
I’ll have to look at a schematic tomorrow for a better idea but on that circuit its either a sensor/harness or possibly an ecm concern. But it shouldn’t be anything horribly in depth to diagnose you want power and ground to be present to the sensor and most likely a third wire for signal
Thanks R4nier!
So I should have mentioned that I did test each port going to the sensor.
Here are the readings I’m hopes those here more familiar can let me know if the readings are appropriate or if there’s an issue:
Blue wire(right port hole): reads 5.08v
Color listed on diagram as R/B with a range from 0.5-4volts
Red wire(middle port hole): reads 0.2-0.3v
Color listed on diagram as B/P with a range of ~0volts
Black wire(left port hole): reads 0.2v
Color listed on diagram as L with a range of ~0volts.
The readings were with truck cranked at idle.
I also noticed that several purchase options came with a replacement harness, but I didn’t order one with this, only the sensor itself.
I also followed the wires all the way to where they connect to the major wiring unit near the transmission and did not see any noticeable issues.
Lastly, I’m located in SE US(NE GA).
I don’t use the truck often for its more of an off road toy, so when it is used, it’s used fairly hard. I last drove it in February on a 700 mile RT excursion, then parked it until May when I identified the limp mode and started researching possible causes.
If you haven't done so already, test all the connector pins on both ends, as well. If you're in the Northeast, for example, you might find that "the green crusties" invading the connectors might be the cause of the problem.
Can confirm "green crusties" over here in the PNW as well.
Also, "green pasties", "green fuzzies", "black slimeys" and a whole lot of "orange flakies"