Fuel Gage upsidedown

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What do you mean cross cables? Do you mean i stick the neg cable in te positive and the postive cable in the negative? Caramel is the best. I love the drive threw big sur. i hope to live in watsonville in te next 5 years.
 
thizzlemania91 said:
What do you mean cross cables? Do you mean i stick the neg cable in te positive and the postive cable in the negative? Caramel is the best. I love the drive threw big sur. i hope to live in watsonville in te next 5 years.
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NOFERGODSSAKE!

Disconnect the negative cable off the battery. Leave positive connected. Place the negative cable on the top of the positive cable (guess what,...it WON'T reach!! OMG what to do!? I use a long screwdriver to make "the bridge" from the neg clamp to the STILL ATTACHED positive clamp). You can also take BOTH off the battery, and then connect one to another (CABLES THEMSELVES, NOT THE BATTERY POSTS!)! There are HUNDREDS of capacitors in all sensors, and other electrical doodads, that retain POSITIVE CHARGE after the battery is disconnected (one reason why ECU keeps things in the memory). Once the cables are crossed, that residual positive charge gets drained to the chassis (ground). No more memory, no more codes,......wipped out!

It's called the "hard reset", and I did it MANY times on all kinds of cars, and the Hippo. Every time I get some codes on ANY vehicle, I clear the codes with the scanner first, correct the problem, and then wipe everything out with hard reset, and start fresh.
 
Oh nice, ill do that then. Thanks for the tips. Ill do a follow up as soon as i get back. I need to take a breather from this thing. Thanks everyone.
 
If you disconnect the battery any residual voltages will die off themselves. Shorting the battery cables together (when at least 1 is disconnected from the battery) is dangerous for electronics circuits. It causes any residual voltage (and therefore current) to flow instantly across a very low resistance. Hence the maximum current ill flow out from where it is. These sudden currents can cause electronics circuits damage. Yes people/garages do it but those who work with electronics cringe when they see it done.

Better idea is to disconnect 1 battery cable and the circuits will loose power. Residual voltage will then decay. Use a volt meter to measure across the 2 battery cables as proof.
 
hippo said:
if you disconnect the battery any residual voltages will die off themselves. Shorting the battery cables together (when at least 1 is disconnected from the battery) is dangerous for electronics circuits. It causes any residual voltage (and therefore current) to flow instantly across a very low resistance. Hence the maximum current ill flow out from where it is. These sudden currents can cause electronics circuits damage. Yes people/garages do it but those who work with electronics cringe when they see it done.

Better idea is to disconnect 1 battery cable and the circuits will loose power. Residual voltage will then decay. Use a volt meter to measure across the 2 battery cables as proof.
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+1
 
Hippo said:
If you disconnect the battery any residual voltages will die off themselves. Shorting the battery cables together (when at least 1 is disconnected from the battery) is dangerous for electronics circuits. It causes any residual voltage (and therefore current) to flow instantly across a very low resistance. Hence the maximum current ill flow out from where it is. These sudden currents can cause electronics circuits damage. Yes people/garages do it but those who work with electronics cringe when they see it done.

Better idea is to disconnect 1 battery cable and the circuits will loose power. Residual voltage will then decay. Use a volt meter to measure across the 2 battery cables as proof.
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This^^^^
You shouldn't simply join battery cables together for the reasons above.
If you want to "kill" all residual power, you must do it with a high resistance discharge. This can be in the form of a 5 ohm resistor across the battery leads or simply switch on the side lights / ignition with the battery disconnected. This will safely discharge any residual power quickly.
 
OK, maybe I was doing it wrong all these years.

Did it on Hippo at least five times since purchase, on L322 twice, on my wife's Jaguar MANY times (don't remember how many), at least 4 times on W220, and several times on Cessna 210. These are just most recent "hard resets" I've done. NEVER had ANY issues because of it.

From 1995 to 2000 I owned a car dealership (VW, Saab, Subaru), and my service department did that after ANY transmission repair/replacement, and this was actually in the Saab dealer's service bulletin.

I don't have a first hand info on the Jaguar Service Bulletin, but was told over a year ago (on Jaguar forum) by a certified Jaguar tehnician (from UK) that this is a NORMAL procedure in Jaguar dealerships.

Disconnecting the both cables, and leaving the battery out of the loop, WILL drain residual charge, and on most vehicles it will take hours, and in some cases overnight. Crossing the cables accomplishes the same thing in 5-10 minutes (it's NOT rapid, OR violent in any way).

So much so, that service department does it right when they start to work on the car (e.g. transmission), and connect it back when done. Tranny needs to learn the new shifting points, and driving habits, as well as throttle pedal possition. ALL "adaptive" vehicle systems (e.g. auto adjustable suspension settings) need to "re-learn" the driver's habbits, and after so many restarts (varies per model), it's all back to "normal".

Anyway. This is MY take on this, and I am not forcing my opinion down anyone's throat. If in doubt, contact your nearest (factory certified) service department and ask them if and how they perform "hard reset" on the vehicles they service.
 
It's not guaranteed to cause damage. It depends on the circuit and how susceptible to damage it is. That doesn't mean if it's worked before it won't cause damage. It's one of those things that can cause harm, but often won't. Bit like jump starting someone's car with your engine running. The spike could cause damage to your car. Loads of people do it and never have problems. One Td4 owner did it on here and killed his engines computer.

Many years ago peeps had a theory of resetting the computer by shorting the wires in order to drain power from the circuit. Theory being the memory would lose it's power and faults wouldn't be remembered. Also the computers program would start from the beginning as it had somehow got into a state where there was a fault and draining power was considered the fix.
 
Hippo said:
It's not guaranteed to cause damage. It depends on the circuit and how susceptible to damage it is. That doesn't mean if it's worked before it won't cause damage. It's one of those things that can cause harm, but often won't. Bit like jump starting someone's car with your engine running. The spike could cause damage to your car. Loads of people do it and never have problems. One Td4 owner did it on here and killed his engines computer.

Many years ago peeps had a theory of resetting the computer by shorting the wires in order to drain power from the circuit. Theory being the memory would lose it's power and faults wouldn't be remembered. Also the computers program would start from the beginning as it had somehow got into a state where there was a fault and draining power was considered the fix.
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This^^^^
In the main dealer I worked in, shorting battery cables together was a disciplinary offence. While as Hippo said, most of the time no damage will be caused, on occasion it can.
Most modern vehicles, the Freelander included, hold adaptive values and faults in non volatile memory. This means that the memory is retained, even after many years without power.
A hard reset can benefit some systems but it's safer to use the side light circuit to do it.
 
Whats the side light circuit? Im going to be cleaning the fuse box and L shape box tomorrow. Cleaning the barrel connections and resetting the codes.
I didnt get a chance to get my meter. So ill have to try this methods first. So were is this side light circuit?
 
thizzlemania91 said:
Whats the side light circuit? Im going to be cleaning the fuse box and L shape box tomorrow. Cleaning the barrel connections and resetting the codes.
I didnt get a chance to get my meter. So ill have to try this methods first. So were is this side light circuit?
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Side lights are the first click on the head light stalk. You might call them parking lights, marker lights or some other name. Putting them on for 10 minutes after the battery has been disconnected will kill all stored power, everywhere.
 
Yeah we call them parking lights. Im going to the shop to get the codes sorted out then clean the fuse box and barrel connection one more time.
 
No luck cleaning codes and hard start. Just keeps messing up when shifting from 1st to second. Ill just have to get a multimeter and check out the resistance. If that seems to be the issue with the solenoid. Ill have to get ride of the car. Because im movin to LA, CA and wont ever have time to be fixing problems that can come up with the freelander :( how hard is it to remove the solenoid? Ive seen hippos video on the plate. But need instructions on this :)
 
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Ok, so i redid the barrel connection resistance and L box commection resistance test and all is fair. Except that brake duty solenoid valve. Also heres another thing . I read on daniels post regarding F4 and rear diff mount being buggy. Could that also do aome harm as my rear diff mount may be going out as well. Just a quick thougts to get into the source of the problem.

Also does the ohms resistance go down after the car has been turned on? Ohm readin on clutch solenoid A, B and seem to be both at 18.6 ohms when car is warm. (Negative battery was off and so was car.) again the brake duty solenoid does not show a reading. Is there a way to bypass this.

Edit: wierdest thing just happened. I was messing with the barrel connectors. 16 pin mostly, but i wnt ahead and used extra force to push connectors in. Plug in negative power cord. And service engine soon light came off ) light was on before due to f4) i got real happy and decided to take it for a spin, but it in reverse and f4 and service engine soon light came on. So maybe just zip tie does dam bastards together will finaly due the trick huh.
 
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Update: what im getting different readings everytime when measuring barrel connectors ad they do not stay constant. Could this be a bad earth connection
 
Yeah i cleaned them, i used two bottles over a three day period. I managed to get my multimeter back and did a resistance check. All show ok but are not ahowing a constant reading. 17.5-17.6 for the shift solenoids A, B, C. Only readings im not getting is from
2-4 brake duty solenoid valve. Ive tried on the barrel connectors and the computer side connector in the L box. All other fuses show a resistance meter and continuaty reading excpet the 2-4 brake duty solenoid.
 
Ok im using this as a reference/diary for anybody that might have incountered this F4 situation. I reset my codes to check what can possibly be the actual deal with this car. I got P1471
P1748
 
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