Stuck in low range

[finallyrangie]

Hello people

As the title says, I have a little issue with getting back into high range.

Had a great day in the glasshouse mountains yesterday, but it ended with me driving at 40kph to my mates place in low.

I have changed the motor and transfer controller quite recently and everything seemed fine, I have got the motor off, do I need to turn the triangular shaft clockwise or anti clockwise to select high range manually?

Thanks as always for any help and suggestions

[finallyrangie]

If anyone ever needs to know, putting 12v straight across the motor positive battery terminal to the yellow wire on the plug winds it into high range.

Now I just need to get rid of the select neutral message so I can hear my indicators again.

[TheTree]

Haven't heard of this one before but I wonder if it is the switches on the gear lever needing a clean?

[finallyrangie]

I will give the switches a look, but I think I might have made it sound more mysterious than it is, we just stuck 12v across the transfer case motor to wind it into high range 'manually ', I am assuming the select neutral message is because the selector is outside of the parameters set by the limit switches on the motor and the ecu can't alter them for whatever reason.

Where is the solenoid that controls the voltage to the motor, we were getting nothing at the plug under the car but lots of beeping in the car, I just assumed the beeping meant the ecu knew I'd asked to change ratio.

I will check the switch, and fuse and solenoid if I can find them.


Ordered another ecu, it's on the way as well

[Rob Hse]

I will give the switches a look, but I think I might have made it sound more mysterious than it is, we just stuck 12v across the transfer case motor to wind it into high range 'manually ', I am assuming the select neutral message is because the selector is outside of the parameters set by the limit switches on the motor and the ecu can't alter them for whatever reason.

Where is the solenoid that controls the voltage to the motor, we were getting nothing at the plug under the car but lots of beeping in the car, I just assumed the beeping meant the ecu knew I'd asked to change ratio.

I will check the switch, and fuse and solenoid if I can find them.


Ordered another ecu, it's on the way as well





Try jumpering a wire from 12 volt positive post on becm to output side of fuse 17 on becm...I had a fault recently which made the shift control module and climate control completely dead,this also in turn put the vehicle in to limp mode when in drive the car would remain in 3rd gear...after doing a bit of research I ran a jumper as described and these items powered up and I had all forward gears as well, only problem was that when vehicle was turned off these items remained energized ,so I ran a wire off the accessory fed white with pink stripe wire to the output side of fuse 17 and everything works fine !....I suspect that I have a broken harness wire somewhere as I had also cleaned all connectors and even swapped becm ,ecu and key fob out of my parts car but the same fault remained ,so I swapped it all back ,then made up the jumper wire ( complete with its own inline 10 amp fuse ) and problem has not come back ,l have traveled around 2500 km since " trouble free !"...hope this helps , cheers , Rob.

Sent from my XT1033 using AULRO mobile app

[finallyrangie]

Found a very useful picture on the interweb showing the connections to the selector motor and the combinations which mean something to the computer.

Took about 25 minutes to inch the motor around with a battery, checking the switch positions after each move until I managed to get it to report it was in high range.

Just put it back on the car, motor says high range and the gear lever says high range, no more error message or limp mode, very happy.

Now I just need the replacement ecu to turn up so I can select low range again!

[3toes]

From memory into low range is achieved via pushing a rod the return from low range requires an electric motor to pull the rod. Into low range is hence easy coming back can be more difficult if this has not been regularly used as the electric motor is not up to the job.

If you are going to use low range and the history of the P38 is not known in regards to low range use is easier to do preemptive maintenance and replace this part before going into low range, If test driving try Low range however warn the owner what may happen if they have not used low range which can then be used as a negotiation point on price.

[finallyrangie]

There seems to be a triangular rod that the selector motor turns either clockwise or anti clockwise to engage either high or low ratio.

The really annoying thing is that I have been through this once already and replaced the motor and ecu, then made a point of using it regularly to keep everything moving, then when I was actually off road it got stuck.

Murphy law I suppose

[finallyrangie]

Replacement ecu has arrived,

And after fitting I can report no change, the damn thing still won't select low range, I will have a proper check at the weekend but I suspect there is no power being delivered to the motor to move it.

Motor moves when powered directly, as I found the high range position manually I would say the switches in the selector motor are working and the ecu is a replacement, there is nothing obviously wrong inside the old one.

Could anyone suggest the next thing to check?

[Keithy P38]

Hopefully it doesn't mean wire tracing for you. Possibly a short or bad earth somewhere?

Cheers
Keithy

[finallyrangie]

I've been trying to find out where the relays are that supply the motor, not even land Rover would put 30 amps through the ecu, not having a lot of luck locating them so far, the internet has let me down.

I fear that tracing wires might be what I'm reduced to!

Thanks for your suggestions people, it helps just knowing it's not just me

[finallyrangie]

Spent a bit of time with a mate and a multi meter this morning, there is no power getting to the shift motor.

The output lines from the transfer ecu are supposed to be either zero or battery voltage but mine seems to be about 9 volts going back to earth with nothing being sent to the motor, does this suggest that the new ecu is fried, could there be something wrong with the motor that kills the ecu, is there anything I can do to check the motor, it turns when voltage is applied directly so I'm assuming it's fine.

There is power to both the fuses 4 and 6, neither has blown

[bblaze]

Had a mazda 626 do that once, put a new ecu in and car didn't even fire. Ended up sending the dizzy and ecu to petrojet and had them both refurbished. Never a problem again. So with a rangie I don't know but with a 626, yes. No help to your problem
cheers
blaze

[finallyrangie]

So one long morning later and I'm struggling.

Power input to the ratio ecu is a good solid battery voltage, 13.8 v with the motor running, all the earths are good and I striped and cleaned the earth points on the body anyway just to be sure.

No matter what happens the output to the change motor stays at 7.9v out of both pairs (so both directions ), according to the testing paperwork it should be zero or battery voltage, which makes sense.

So what are the chances that all three (yes three ) later model ecu units have all failed in the same way with no visible sign of damage, I've opened them all up to check.

When I move the gear lever over the h gate I get all the appropriate beeping and light flashing, but no voltage reaching the plug at the transfer motor and the strange 7.9 v output from the ecu.

If anyone has any suggestions I would be very grateful, the boss has started talking about Toyota and I'm starting to run out of arguments, why couldn't land Rover have made it properly, it would have ruled the world !

Thanks a always for any suggestions, hints or advice on how to hold my tongue.

[mtb_gary]

Mine is currently stuck in high range with the select neutral disp,layed. Just prior to the error there was a burning plastic smell and smoke in the cabin from around the passenger side footwell. I'm suspecting the 2 are related hopefully just a microswitch or similar. Whenever I try to change to low range the burning smell reappears. No serious off roading on this holiday, it's going to be high range all the way. (I'm currently in Exmouth 1250 k's from home). Once home I'll be taking apart the console to see what's melted.

[finallyrangie]

I found it was very easy to "hot wire " the selector motor to move between the ranges, it took a little while to find the correct position for the switches though, and that's what gives the select neutral message. Mine would Change gear at 2500 rpm no matter what with the message up , but it's not that difficult to inch it round until the correct switch combination comes around.

I'm thinking of making an overide out of a ride height rocker switch, it has 4 lights and there are 4 sensors on the shift motor, I'm wondering how hard it would be to be able to see if the sensors are open or closed and manually set it up in the right place.

I feel another project coming on

[mtb_gary]

I think I've found the source of the burning smell

[finallyrangie]

I think I've found the source of the burning smell



Well that looks fairly definitive, is the motor still alright, if it is a replacement ecu isn't topainful.

[mtb_gary]

Well that looks fairly definitive, is the motor still alright, if it is a replacement ecu isn't topainful.

The motor had been working fine. I'll find out for sure tonight when I put the replacement ECU in

[finallyrangie]

It might be worth just checking the motor with a battery across the terminals before you fit the ecu, I have read that one of the two not working can damage the other.

Hope that's all it is

[mtb_gary]

I picked up the replacement ECU yesterday but unfortunately it was for an earlier model. Before fitting I took off the cover....totally different insside. I'll have to search for the correct part. I will check the motor before fitting

[finallyrangie]

I understand that the older ones will work just the same, as long as it's for an auto, but I think the older ones are less reliable than the newer options.

It's a pity you're not closer, I have several you would be welcome to try

[mtb_gary]

Correct part on its way from UK ?15 for the part and ?18 for air freight delivery. (Around $56 all up). I also replaced the selector motor today. It had seized completely, I suspect it is what caused the melt down in the first place. The car is still drivable just not in low range at present.

[Scouse]

When these cars were relatively new, the info from LR was that these usually fail together.
Either the ECU fails burns out the shift motor by over cycling it or the motor seizes & fries the ECU while it tries to operate it.

[finallyrangie]

Okay, so I bit the bullet and replaced both the ecu and the shift motor in one go, still no difference.

The thing that is confusing me now is the output from the ecu, the 12v output to change the ratio should be either 12v to move the motor or 0 if it needs to stay still, but both directions (4 wires ) are all showing 8v all the time, could that be an issue with the becm or could I still be looking for a bad earth, there seems to be 12v to both of the input lines, I will be running another supply from the post on the body computer at the weekend to double check but any other suggestions greatly appreciated, I'm running out of ideas

[finallyrangie]

So I have run power directly to the transfer ecu from the becm, on the positive side it's ruled that out as the problem, on the down side of course, still no closer to a solution.

The search continues

[mtb_gary]

So I have run power directly to the transfer ecu from the becm, on the positive side it's ruled that out as the problem, on the down side of course, still no closer to a solution.

The search continues








Just a thought. What position is the selector in physically inside the TC? Is it the same corresponding position on the selector motor? From what I've read the switches that determine the position are in the reduction box on the TC sepector motor.

Have you tried the TC selector motor operation before installing. Just simply plugging in the cables?

Do you get any messages on the dashboard?

[mtb_gary]

So I have run power directly to the transfer ecu from the becm, on the positive side it's ruled that out as the problem, on the down side of course, still no closer to a solution.

The search continues








Just a thought. What position is the selector in physically inside the TC? Is it the same corresponding position on the selector motor? From what I've read the switches that determine the position are in the reduction box on the TC selector motor.

Have you tried the TC selector motor operation before installing. Just simply plugging in the cables?

Do you get any messages on the dashboard?

[finallyrangie]

Just a thought. What position is the selector in physically inside the TC? Is it the same corresponding position on the selector motor? From what I've read the switches that determine the position are in the reduction box on the TC selector motor.

Have you tried the TC selector motor operation before installing. Just simply plugging in the cables?

Do you get any messages on the dashboard?


I did get a message on the dashboard when I wound the motor back into high but I took the motor off and used a battery to turn it, checking the switches as I went until I got it to report high range position, (from memory 1,2 and 4 open and 3 closed ,then put it back together and no error messages.

Motor turns in both directions and all the switches seem to work as they should, that's what is so frustrating, motor works and the computer appears fine apart from putting out 8v to the motor instead of 12v or nothing, and changing the ecu gives exactly the same result.

I am genuinely at a loss

Apart from this my p38 is actually running pretty good at the moment

[mtb_gary]

As you suggested. If you are only getting 8v there is a loss somewhere in the system. Al i can think as the next step would be to check the resistance of each of the supply wires and connectors until you find the culprit

[finallyrangie]

The problem is that I get 8v out of all 4 output wires all the time, multi meter across all the other input and output wires seems to be as suggested by the diagnostic plan I've got, but the output to the motor is always that value regardless of whether it's being asked to change ratio.

That's why I've ended up with so many ecu units, but whilst I was willing to accept even a couple being faulty the same way, 4 seems a bit unlikely, and they are all the newer version so should be more reliable.

I might actually have to pay someone to fix it at this rate, and I don't think that's going to be a cheap option.

Thanks for all the suggestions, anybody else had any experience with this problem?

[mtb_gary]

I'm pleased to report mine is working again but not without some grief from a second hand ECU I purchased out of UK as "in working order when removed from the car"......sounds familiar? Before putting it in my car I decided to remove the cover, and sure enough there were signs of getting very hot. On seeing the singe marks on the board I decided not to risk it and have since purchase the most recent version locally here in Perth.

Finallyrangie, have you taken the cover off the ECU as a visual inspection?

[finallyrangie]

Well done, glad you managed to get everything working again.

I've had the cover off of three of the ones I've got, there doesn't seem to be any visual evidence of any problems, but I am happy to admit I'm no Electronic genius, the pictures I've seen of damaged ones on the Web do seem to be quite blatant though.

I'm not going to give up, just not sure how to proceed.

[mtb_gary]

Well done, glad you managed to get everything working again.

I've had the cover off of three of the ones I've got, there doesn't seem to be any visual evidence of any problems, but I am happy to admit I'm no Electronic genius, the pictures I've seen of damaged ones on the Web do seem to be quite blatant though.

I'm not going to give up, just not sure how to proceed.






Where are you taking your voltage measurements from?

[finallyrangie]

I have a trouble shooting guide downloaded from somewhere, the 12v going in and all the earth connections seem to be correct, there are 4 larger wire connections in pair above and below the 12v input wires, these I believe power the transfer case motor in each direction, one pair clockwise, the other anti clockwise, these according to the paperwork should be either 0 or 12v, which seems perfectly logical, except they give 7.9v out of all 4, apparently all the time.

This suggested to me that the ecu was cactus, but I now have 4 that all give the same result, so I'm trying to figure out what could cause that outside of the computer.

[finallyrangie]

I have a trouble shooting guide downloaded from somewhere, the 12v going in and all the earth connections seem to be correct, there are 4 larger wire connections in pair above and below the 12v input wires, these I believe power the transfer case motor in each direction, one pair clockwise, the other anti clockwise, these according to the paperwork should be either 0 or 12v, which seems perfectly logical, except they give 7.9v out of all 4, apparently all the time.

This suggested to me that the ecu was cactus, but I now have 4 that all give the same result, so I'm trying to figure out what could cause that outside of the computer.

[finallyrangie]

Okay, rather than keeping on with the same thing, could it be a problem with the speed sensor on the transfer case?

I'm looking for other possibilities, as I've tried the ecu and motor change and got nowhere.

Is that the 2 bladed sensor on the back of the transfer case or is that a temp sensor?

So many sensors butit can't tell me what's wrong!

[mtb_gary]

I'm not sure what documentation you have. But here are the extracted pages from RAVE. Good luck!

[finallyrangie]

Thanks for the documents, almost the same as the ones I've got but it never hurts to read it again.

I'm waiting for a new speed sensor to get here this week and I will try that, this issue might have to take a back seat as the dreaded death wobbles appeared at the weekend, it never rains!

[mtb_gary]

Hopefully nothing too serious for the death wobble cure

[finallyrangie]

Death wobble sorted, turns out that although the new panhard rod bushes were fine after they were fitted, a big morning off road must have given them a bit more space, the bolts are now "metal worker of 30 years with a 2 foot breaker bar" tight, and all is well.

On the low range front it would appear that land Rover have stopped producing the speed sensors, so I'm trying to find someone who actually has one, at a decent price. All good fun!

[finallyrangie]

So I got a new speed sensor, and fitting it didn't change anything so I started looking for something, anything else.

I tried another complete change of computer and transfer case motor, clutching at straws, did me no good.

Today I decided to check the plug on the speed sensor, , it was fine, but I spotted a damaged wire, it looks like the plastic retaining clip came loose and let the wire from the speed sensor touch the handbrake drum,

5 minutes with a soldering iron and low range in 3 beeps, reliable as clockwork, I am a very happy cha

Now what do I do with 4 perfectly good transfer case computers?

[Keithy P38]

eBay!!!!

Nice (and long overdue) find mate!

Cheers
Keithy

[lauriellila]

If anyone ever needs to know, putting 12v straight across the motor positive battery terminal to the yellow wire on the plug winds it into high range.

Now I just need to get rid of the select neutral message so I can hear my indicators again.







Thank you for this information, I am making my own controller for range selection motor - have you got the pin arrangement what the other wires there are?