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Pete, Technician
Category: Jeep
Satisfied Customers: 28743
Experience:  Over 17 years diagnosing and repairing automobiles various makes and models with some training and certifications.
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I have a P0720 code came recently and ABS light is on< I

Customer Question

HI I'm Sergey, and I have a P0720 code came recently and ABS light is on< I have Cherokee CDR 3L diesel
JA: Thanks. Can you give me any more details about your issue?
Customer: at the beginning ABS light came on, and I could still drive normally, after a day such driving check engine showed up and the car went into limp mode. I have changed ABS sensor (right rear) and can drive it again normaly, however ABS light is still on and computer says "service 4WD", I have checked differented sources and the only I could think about its transmission speed sensor, but I inspected my transmission all around and could bot located any sensors on it. Do they even exist on my vehicle? and where else to look to get rid of ABS light
JA: OK got it. Last thing — Jeep Mechanics generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: Jeep
Expert:  Pete replied 1 year ago.

My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.

The first thing that needs done here if this has not been done yet is to have the codes cleared out then operate the vehicle and see if the code comes back at all.I would also make sure you are checking for fault codes with a scan tool plugged into your vehicle that can communicate with all computers in your vehicle as some scan tools are not able to communicate with all computers and there may be other codes set with this issue here that need diagnosed.If you can double check to see if any other codes are set this will help.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 1 year ago.
I have cleared the code, it goes away, but just for a second and comes back right away P0720
Expert:  Pete replied 1 year ago.

Can you tell me the year of this model here?

Customer: replied 1 year ago.
2008 grand cherokee L3 CRD Diesel
Expert:  Pete replied 1 year ago.

O.k.,this code indicates a fault with the transmission speed sensor.The speed sensors look to be inside the transmission attached to the shell of the valve body.If the speed sensor has not been replaced I suspect this is the cause here needing replaced.This may require some special tools in some cases to access and replace this sensor.

Let me know if you need anything else and feel free to rate my help here.

Thanks Pete

Customer: replied 1 year ago.
I wonder if you have drawings where specifically that sensor is located, since I have crawled all around my trany and could not locate anything
Customer: replied 1 year ago.
have to run, but your reply would be gratefully appreciated, thanks, Pete
Expert:  Pete replied 1 year ago.

I apologize for the delay.

The only info I show on this here is they are #6 and #8 in the diagram below and are inside the transmission.

The speed sensors, N2 and N3, (6, 8) are fixed to the shell of the electrohydraulic control unit's leadframe via contact blades. The speed sensors are pressed against the transmission housing (2) by a spring (7) which is held against the valve housing of the shift plate (5). This ensures a defined distance between the speed sensors and the exciter ring (4).

Thanks Pete