[Jonetra]

I bought a non running 2003 Discovery a while ago. I've been living on, under, and in it for the past 8 weekends getting it back up and running. I finally got it close to run. I have two codes popping up: P0505 and P0722. As for P0505, I just cleaned the IACV. I believe P0722 means no signal from the speed sensor. Does this mean I need to replace this sensor?

Anyone have any suggestions on how to remedy these two codes??

 

[Disco Mike]

Also clean the t/body. As for the 722 code, down load a free copy of the Rave CD, shop manual and read up on the speed sensor in the tranny repair section.

 

[Jonetra]

Also clean the t/body. As for the 722 code, down load a free copy of the Rave CD, shop manual and read up on the speed sensor in the tranny repair section.

I have the RAVE CD. Unless I'm just missing it, it only mentions the 722 code and its symptoms. I haven't found anything that would tell me how to repair or even troubleshoot 722. I have another speed sensor and thought that replacing the speed sensor might do the trick.

 

[Disco Mike]

Usually I at least read up on the issue. As for the speed sensor, it is internal in the valve body and as far as I know, there is no way to rebuild it.

 

[jafir]

P0722 says "Torque converter slipping" which sounds like a transmission replacement or rebuilt to me. You could try changing the fluid and filter, I guess.

 

[Disco Mike]

Looking at my 4 sets of Rover fault codes, 2 show it to be a speed sensor the other 2 show it as a slipping TQ.
I don't know what direction to point him at this point.

 

[jafir]

Looking at my 4 sets of Rover fault codes, 2 show it to be a speed sensor the other 2 show it as a slipping TQ.
I don't know what direction to point him at this point.

Yeah, I was just going by what it says in the copy of RAVE I have. It also indicates that the M and S lights should be on, along with the check engine light. If that's not what happening, maybe the codes are old. Maybe they should just be cleared and see if they come back.

 

[Disco Drew]

I bought a used 99 Disco, and it has the same PO722 code. I knew that it had transmission problems when I bought it. Mine will shift into reverse, but not any of the forward gears. I have talked with several transmission shops and Land Rover specialists and they all concur that the forward clutch pack is fried. When the speed sensor doesn't register from the clutches slipping, it throws that code. I know that in the rave manual it says torque converter slipping, but mine has reverse and I know that it isn't the torque converter. I was quoted 4,000 - 4,700 for a rebuild and 1200 - 1700 for the install. I bought a used one from a running truck for 300.00 and I'll install it myself. There is no chance that I would put 5,200 + into a truck that has a resale value of about 3500! I hope that helps.

 

[Disco Drew]

I forgot to mention that on mine, the M and S lights do not come on until you rev the engine up to a certain point. I think that if yours drives, but is in limp back home mode, there is a chance that it is a bad sensor. From what I have heard, slipping of the clutches can also trigger the PO722 because it is monitoring the output speed. Maybe a transmission expert could confirm?

 

[Jonetra]

I does drive in all forward modes and has reverse. The M and S lights do not come on, only the check engine light.

 

[Disco Drew]

If it were mine, I would print out all of the current codes, then erase them all. That should make your check engine light turn off. Drive it around, then 'when and if' the check engine light comes back on, check the codes again. If the PO722 code keeps popping up, I would replace the sensor in the valve body and when replacing the transmission oil, I would add either lucas transmission additive or barrs transmission additive (the stuff with two fluids in the bottle.. I run 7 snowplow trucks and that stuff has kept a tranny alive for a few seasons). If it keeps triggering the PO722 code, get out your wallet or plan on replacing the transmission.

 

[Jonetra]

It was the sensor. I did clear all the codes and the 722 and 505 codes kept coming up. I went ahead and replaced the sensor and now I just have the 505 code coming up. Anyone have any thoughts on this code. I just cleaned my IACV and throttle body.

 

[Disco Drew]

Great news Jonetra! Please update us in a few weeks if the code pops back up, or if it is gone forever. Thanks!

 

[Disco Mike]

505 is an idle air control issue.
How did you clean the idle solenoid, be specific?

 

[Jonetra]

I pulled it off and sprayed it with carb cleaner and made sure the valve was free.