P38A Stuck in low range

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So.. could the potentiometer in the motor be at fault?
Maybe the chance of trying another motor could help rule out that end of the chain? (So to speak).o_O
Could it be checked with a meter for resistance on the relevant wires..
 
Mark Piercy said:
So.. could the potentiometer in the motor be at fault?
Maybe the chance of trying another motor could help rule out that end of the chain? (So to speak).o_O
Click to expand...
possible - and I think I was wrong, it is not a pot but a series of switches....in any case, I am not sure that is the fault, as the ECU thinks it is in a drive range, and that you have commanded a ratio change but the gearbox is not in neutral....

I am sure RAVE has a pinout showing what switches or readings should be available from the transfer box motor for each drive range and is worth a looking at.
 
Mark Piercy said:
Question is, what why would the ECU think it's in neutral (transfer box) if you can't actually select neutral from the gear lever? Only by putting a fuse in slot 11 in the seat fuse box??
:eek:
Click to expand...
I can select neutral, when I do the message goes, but it will not drive as its in neutral. :-(
 
Saint.V8 said:
The ECU thinks that you are changing ratio and as such needs you to select N.

Have you tried selecting N, then changing to low and then back into high again?

It may be that the ECU still thinks a ratio change is in progress
Click to expand...
Makes sense, but if this was the case would it continue beeping and flashing the gear light?

I have not gone back to low yet fearing it will jam again and I need to take it off and start from fresh. When I have more time I will give it a shot. Probably after work.

Cheers
 
Right well it is broken again. Stuck in low.

I selected low as suggested, it changed, all ok, went to move back to high and it is jammed. Same as original post.

Total nightmare and getting frustrated.

I cannot see how this is the switches as that surely only tells the ECU which range/gear it is in. Which works fine. All are selectable and all are displayed on the display.
Neutral works too, the sensor for neutral knows when it is in that position as it tells me and the message goes.

Has nobody had this problem before?

Again the problem is moving from low to high, it does not complete the move and stays in low.
The motor spins manually with 12v applied.
I can manually select high removing the motor.
After all this I get select neutral constantly.
 
JamesBB said:
Right well it is broken again. Stuck in low.

I selected low as suggested, it changed, all ok, went to move back to high and it is jammed. Same as original post.

Total nightmare and getting frustrated.

I cannot see how this is the switches as that surely only tells the ECU which range/gear it is in. Which works fine. All are selectable and all are displayed on the display.
Neutral works too, the sensor for neutral knows when it is in that position as it tells me and the message goes.

Has nobody had this problem before?

Again the problem is moving from low to high, it does not complete the move and stays in low.
The motor spins manually with 12v applied.
I can manually select high removing the motor.
After all this I get select neutral constantly.
Click to expand...
I think the high/low motor has to be set up with diagnostics..
 
Ok, plug the motor into the range rover but not mounted to the transfer casing. If it goes through the motions when you select hi and lo, you could have a sticking transfer box or a weak motor?
But... If you can change from hi to lo on transfer casing via hand easily, it would suggest a weak motor. Is there any way while the motor is on your bench to get it to move under strain?;)
 
In the distant past I read somewhere that the ratio motor needed to be set with diagnostics. I've changed a few and never needed to. With motor off select high,turn shaft to engage high then fit motor.
 
tomcat59alan said:
I checked Rave and it doesn't mention diagnostics.
Click to expand...
was just about to say the same....

To the OP....when you set the transfer motor to the required range manually using a 12V supply - how did you determine the correct ratio position? Did you use the 4 switches and read the open close status of each to determine correct position?

As there is Left Stop - Left of High - High - Right of High - Zone 1 - Neutral - Zone 2 - Low Range - Right Stop......
 
Saint.V8 said:
was just about to say the same....

To the OP....when you set the transfer motor to the required range manually using a 12V supply - how did you determine the correct ratio position? Did you use the 4 switches and read the open close status of each to determine correct position?

As there is Left Stop - Left of High - High - Right of High - Zone 1 - Neutral - Zone 2 - Low Range - Right Stop......
Click to expand...
I am not sure what these positions are. Is it explained in Rave?

The transfer box shaft moves to 2 positions only?
I spun the motor with DC applied until it lined up with what looked to be the high position. That worked, except for the select neutral and that it will not come out of low.

Not sure if the SN message went when it was in low. I will try again tomorrow, but I think it did go from memory.

Cheers
 
JamesBB said:
I am not sure what these positions are. Is it explained in Rave?

The transfer box shaft moves to 2 positions only?
I spun the motor with DC applied until it lined up with what looked to be the high position. That worked, except for the select neutral and that it will not come out of low.

Not sure if the SN message went when it was in low. I will try again tomorrow, but I think it did go from memory.

Cheers
Click to expand...
t/box selector shaft has 3 positions, faults are usually motor or t/box ecu
 
I had this problem but the other way around, wouldn't select low. It would move into neutral and back to high but wouldn't go into low. I ended up changing the motor for a s/h unit £20 on flea bay and all is fine now so put it down to a weak motor. Hth
 
JamesBB said:
Right well it is broken again. Stuck in low.

I selected low as suggested, it changed, all ok, went to move back to high and it is jammed. Same as original post.

Total nightmare and getting frustrated.

I cannot see how this is the switches as that surely only tells the ECU which range/gear it is in. Which works fine. All are selectable and all are displayed on the display.
Neutral works too, the sensor for neutral knows when it is in that position as it tells me and the message goes.

Has nobody had this problem before?

Again the problem is moving from low to high, it does not complete the move and stays in low.
The motor spins manually with 12v applied.
I can manually select high removing the motor.
After all this I get select neutral constantly.
Click to expand...

So just to summarise.

If you manually turn the transfer box to high and reassemble then it drives fine in High except the message centre says select neutral.
It will go into transfer box neutral (no drive) with no error messages.
It will go into Low range fine and drive fine in low range.
Once in Low it doesn't come out again but will drive around fine in all the gears?

If RAVE doesn't have the pins and switches the Nanocom documentation might.
 
Grrrrrr said:
So just to summarise.

If you manually turn the transfer box to high and reassemble then it drives fine in High except the message centre says select neutral.
It will go into transfer box neutral (no drive) with no error messages.
It will go into Low range fine and drive fine in low range.
Once in Low it doesn't come out again but will drive around fine in all the gears?

If RAVE doesn't have the pins and switches the Nanocom documentation might.
Click to expand...
RAVE does have the pin connections and also a switch matrix to show what switches should be doing what at each of the motor movement stages.
 
Grrrrrr said:
So just to summarise.

If you manually turn the transfer box to high and reassemble then it drives fine in High except the message centre says select neutral.
It will go into transfer box neutral (no drive) with no error messages.
It will go into Low range fine and drive fine in low range.
Once in Low it doesn't come out again but will drive around fine in all the gears?

If RAVE doesn't have the pins and switches the Nanocom documentation might.
Click to expand...

Yes that is correct. Weird stuff.
 
Saint.V8 said:
was just about to say the same....

To the OP....when you set the transfer motor to the required range manually using a 12V supply - how did you determine the correct ratio position? Did you use the 4 switches and read the open close status of each to determine correct position?

As there is Left Stop - Left of High - High - Right of High - Zone 1 - Neutral - Zone 2 - Low Range - Right Stop......
Click to expand...

Hi

Any advance on this? To the OP....when you set the transfer motor to the required range manually using a 12V supply - how did you determine the correct ratio position? Did you use the 4 switches and read the open close status of each to determine correct position?

As there is Left Stop - Left of High - High - Right of High - Zone 1 - Neutral - Zone 2 - Low Range - Right Stop......

Problem being I really am not sure what you refer to......... Thanks again.
 
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