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R75CDT rev counter temp gauge HRW fault

4K views 16 replies 4 participants last post by  Charlie Hall 
#1 ·
Hi,
I have a 2001 Rover 75 CDT Club and have had an intermittent problem for several weeks with all 3 of the items in the title, and gradually worsened to the point they now never work. In the beginning I was driving in damp foggy weather and noticed the rev counter reading zero and only intermittently working, then noticed whenever that happened the temp gauge did the same, then later still I noticed the heated rear window did not work when the others did not. When the rev counter did decide to work the other 2 items always worked. So I believe there is one common fault affecting all three items.
I took it to the local garage who I trust because one of my best friends is a mechanic there and previously between his knowledge and messages found in this forum, was able to fix all my fuel problems without making costly errors with guesswork.
He says he has today tested it with a scan and got an error code E0100 and he said what it meant but as I understand it these messages are often cryptic. He also says he cannot locate the fault without a wiring diagram but thinks it could be one of 3 things, a bad connection within a connector, a bad earth, or a faulty ECU I think he said (apparently there are several ECU systems in the car?).
I am hoping that someone here might have an idea of the most likely cause of this problem?
In the meantime I can look for a wiring diagram and would also like to know if anyone can tell me if the Haynes manual would include all necessary diagrams.
Thanks to all in advance for any help.
Charlie Hall
 
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#3 ·
you can check the dial work on your dash

press the trip hold in trune key to pos 1 or 2 the display reads test 1._

press till reads 2._

let go od trip wait

reads 2.0

wait 1 sec press trip

all warning light bar , abs and air bag i believe come on , and all dials go through a sweep

from mem this is , if not working for you giz a shout ill tell you after playing with my car
 
#5 ·
Charlie,

I really wouldn't wait at all. If there is water in there and it rises just a few more millimetres then your ecu-aka the bit that makes everything work!- could be taking a big bath that will cost you Big££ and lots of no car time to put right.

It really is better to sort it before you get to that stage.

Regards

Mike
 
#9 ·
I guess it could be that as I had wondered the same thing. My problem is I don't know how to get to it! I'll have to leave it to my mechanic friend to check it out once I have the service manual as I'm not as DIY inclined as I was in my younger days. Thanks for the suggestion and I'll keep it in mind to tell him.
Charlie Hall
 
#10 ·
its easy mate , at the top of the dash there is a piece of plastic take the 2 crews out lever gently out then at top of the dash its self 1 scre then the dash pulls gently out

if you discconect any wires you might get a -30 on the temp dispaly if this happens unplug for 5 more mins

the cables dont just push into the back there is a locking lever on the connector

out of intrest do the dials sometimes work ?

stop working after a bump ?

stoped working due to protest about the cold ?
 
#12 ·
Thanks for the information to remove the dash. I think I will try that on Sunday. The affected dials and HRW did work intermittently but never do now. I never noticed any bumps having an effect. It seemed to be more to do with damp weather, as after the first time it happened the weather got better and everything worked OK for a few days until the weather changed again. I don't think it is so much to do with the cold as it is the damp.​
I don't fancy disconnecting the battery at this stage as I don't know what resets if any might be involved. I know the radio cassette would need resetting but I can do that.​
Thanks for all the suggestions, they certainly are helping.​
Charlie Hall​
 
#13 · (Edited)
when you checked the drain holes did you pour water down and make sure it drained away as per the clubs instutions ?

id also as a last resort check all fuses under glove box etc as there are a few labeled instruments

also the body contolr unit which is behind the glove box , could be a loose wire or a faulty unit itself , get your self down to a dealer mate , get it plugged into testbook and see what the computer says or i think youll be chasing your tail
 
#15 ·
chilljohn,
No, We didn't pour water to check. I will make sure that is done soon. I will also check the handbook for fuse information. What is testbook? Is it something only Rover MG dealers have and different to the scanner my mechanic would be using for example?
Respot,
I will also try disconnecting the battery and see what happens.
Thanks again.
Charlie Hall
 
#16 ·
tesbook is the software the techs us at the dealer its wrote specially for the car so has lot of options and the ability to test all the units in the car not just read the ecu fault codes it also lest you configer the onboard computer for example the folllowing options
Daytime running lamps on or off (aka VOLVO!)
Speed locking on or off
Lazy lock and vent (using the door key only) function on or off (open windows or shuts them via key you hold key in lock or unlock and the windows open or close this is good for the summer i find)
Single point entry (one press to open drivers door, second press for rest)
Headlamp delay on or off
Tail lamp delay on or off
Number plate lamp delay on or off
Intelegent wipe (wiper speed goes down a notch under 5 mph) on or off
Programed wash wipe (no program or 2,3 or 4 wipes)
One shot down on or off
One shot up on or off (drivers window only with 4 electric windows)

i was reading the how to bit of the forum and there is a bit in ther etelling you how to test the dash like i said it says that if the test passes like you said it did the dash is fine and its more than likly a problem with one of the other modules and it gives a few more test to try and narrow it down, the below is a direct quote from that thread (might help >)

K-Bus communication to Light Switch Module (LSM)
Turn the hazard warning lamps on, if the direction indicator lamps in the instrument pack operate, then the K-Bus communications between the Light Control Module (LSM) and the instrument pack is functioning correctly.

K-Bus communication to Body Control Unit (BCU)
Open any door with the ignition switch in position 'II'; if the door open warning lamp is illuminated, then the K-Bus communications between the Body Control Unit (BCU) and the instrument pack is functioning correctly.

K-Bus to CAN-Bus gateway
Start the engine and switch the air conditioning on. Open the bonnet and monitor the operation of the air compressor clutch; if it is cycling on and off (pulley rotates then stops) then the K-Bus to CAN-Bus gateway is functioning correctly.

CAN-Bus communication to Engine Management ECMs
Start the engine, if the tachometer displays the engine speed, then the CAN-Bus communications between the ECM and the instrument pack is functioning correctly.

CAN-Bus communication to ABS ECU
For vehicles with ABS and traction control, turn the ignition on. If the traction control warning lamp or message is illuminated, then the CAN-Bus communications between the ABS ECU and the instrument pack is functioning correctly.

CAN-Bus communication to Electronic Automatic Gearbox (EAT) ECU
Turn the ignition on, if the PRNDL display in the trip computer / odometer changes gear in accordance with the gear selected, the CAN-Bus communications between the electronic Automatic Gearbox (EAT) ECU and the instrument pack is functioning correctly.

NAV-Bus
Turn the ignition switch on and close all the doors, and wait until all the large icons have been displayed. Select navigation by using the relevant navigation controls. If the navigation information is displayed in the message centre, then the NAV-Bus communications between the Navigation Control Unit and the instrument pack is functioning correctly.





ps i know i keep saying it but dont forget to check that water flows down the drain holes , i just hear alot of desils suffer thats all good luck mate but to be honest i think it will be easirer in the long run to pop this baby to a dealer, providing the battry disconect etc doesnt work get it while its early on might save a bit of cash
 
#17 ·
chilljohn,
Thank you very much for confirming what testbook is and those test details.
Circumstances dictated that I was not able to do any of my planned tests today.
Therefore I will print off this entire thread and let my mechanic see it.
Thank you again.
Charlie Hall
 
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