[JasonF]

Hey!
I took my 2016 Jeep Cherokee Trailhawk to garage to have the crank shaft sensor replaced (scan code confined)! To my surprise, after 6hrs of labour, the engine light was on (wasn’t when I pulled in) and they confirm the issue likely has not been resolved as they can’t clear the code! They didn’t check wires etc, just replaced the sensor (as requested by us)! $520 later, my 4X4 system is not working, it won’t shift (rpm’s won’t go below 3000),and can’t get in into reverse. Any idea what they did? Something with the transfer case? Transmission? Something not hooked back up!? So frustrating!

 

[Dodgeboy 1969]

You did the number two NO NO. Never tell a shop what to do. I don't care what your scan tool said, you use that if you are going to diag. and fix it yourself. Many things can throw 1 specific code. Should have told them what it was doing, and what you "Think" might be the problem, if you want to, but let them diagnosis it and tell you what they found.
Number one NO NO, drop the car off let them diagnosis it and start work and then tell them to put it back together, your "friend" will do it cheaper. I would put Loctite on ever nut, bolt and spark plug I put back in after that.

 

[rumrunner]

too bad they can still charge us for stuff they do by mistake

 

[Dodgeboy 1969]

too bad they can still charge us for stuff they do by mistake

if he dropped the car off with a sensor and told them to install it, how is it the shop's mistake?

 

[Gary Kline]

Hey!
I took my 2016 Jeep Cherokee Trailhawk to garage to have the crank shaft sensor replaced (scan code confined)! To my surprise, after 6hrs of labour, the engine light was on (wasn’t when I pulled in) and they confirm the issue likely has not been resolved as they can’t clear the code! They didn’t check wires etc, just replaced the sensor (as requested by us)! $520 later, my 4X4 system is not working, it won’t shift (rpm’s won’t go below 3000),and can’t get in into reverse. Any idea what they did? Something with the transfer case? Transmission? Something not hooked back up!? So frustrating!

Do you have the original sensor where it could be put back in? My personal concern... The crankshaft sensor is a very important part. The Cherokee's ECU uses the output from that as well as the two camshaft sensors (actually there are four camshaft sensors, two on each physical sensor ) to know the position of the crankshaft and cams in relation to each other to increase or retard the timing of the VVT system. Part of the high RPM issue I bet could be from misreading the sensor output. If I had to take a guess, the ECU/TCU is not letting the 4WD system or Reverse engage because the RPMs are so high (imagine driving in reverse at 3k RPMs)!

(a) did the correct sensor go in? (e.g. absolutely sure it was the correct Mopar part number?)
(b) when replacing any part of the crank/cam relationship (sensors, physical components etc.) , there's a process called a "Cam/Crank Re-learn" that needs to be done. It tells the ECU to erase stored values and collect a set of new ones. Any idea if this was done?
(c) if the original sensor still available? If there's any chance it wasn't discarded, grab it and save it.

 

[Gary Kline]

This is the option on my AlfaOBD to use when a cam sensor, crankshaft sensor, camshafts or any other part of the engine timing system (sprockets, timing chain [if ever] etc.) are replaced.

or

2. Appcar DiagFCA