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Discussion Starter · #1 ·
I have just changed my water pump and cambelt and now I cannot get the car to start.

The car has been off he road for a while and the battery is flat so I tried jump starting it with my land rover but it wont turn over. The dash lights come on but when you turn the key nothing happens. If I leave the key in the on position the dash warning lights flash continuously until I switch off again, then the speedo needle vibrates for about 3 seconds. It seems like the immobiliser has kicked in as it won't even try to turn over.

I can turn the engine over by hand on the crankshaft pulley quite easily and I have triple checked that the timing marks still line up top and bottom and as I used the proper locking tools I am happy that everything has come apart and gone back together fine. I can also lock and unlock the car on the remote so there is still enough juice in the battery to activate the central locking and alarm so I would have thought the immobiliser would activate and deactivate as well.

I don't have access to VAGCOM so I'm not sure what I can try next. Can anyone help?
 

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Discussion Starter · #3 ·
Hi Chris,

I can hear a click, not sure if it is the starter. From in the car it sounds like a relay.

I have taken the battery off now and will leave it on charge overnight to see if that helps, but like you said a jump start should have got it moving. I've never had a problem like this before it's a real head scratcher.
 

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if the battery was that flat then the jump leads will struggle to put enough in the battery to crank it over, as above try charging it and have another go, im sure that after a full charge it will be fine mate
 

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Doesnt matter. The electric doesnt need to go through the battery.

Jump leads would have almost certainly made it turn over at the least.

Maybe starter motor is jammed? Put it in gear and try rocking it back and forwards or hit it with a hammer. Sometimes works. Check the connections too
 

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Doesnt matter. The electric doesnt need to go through the battery.

Jump leads would have almost certainly made it turn over at the least.
if a battery is dead flat the jump leads will have to be connected and left for a bit just to put a little life in the battery, if not then there is very little chance the starter on a diesel will do anything other than click, but then what do i know

ive only been a qualified mechanic for 18 yrs
 

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Im not mocking your knowledge,

Just electric comes from the highest potential, so would be the other car in this case.
but putting a flat battery in the middle will cause a massive voltage drop, in other words the flat battery will take most of the voltage from the leads before sending it on to the starter motor, its very common on a diesel for this to happen, bear in mind on say a D5 diesel engine if its got less than 12.3 volts in the battery it will hardly turn over, also over the jump leads there will be a voltage drop altho low will also make a difference
 

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I have just changed my water pump and cambelt and now I cannot get the car to start.

The car has been off he road for a while and the battery is flat so I tried jump starting it with my land rover but it wont turn over. The dash lights come on but when you turn the key nothing happens. If I leave the key in the on position the dash warning lights flash continuously until I switch off again, then the speedo needle vibrates for about 3 seconds. It seems like the immobiliser has kicked in as it won't even try to turn over.

I can turn the engine over by hand on the crankshaft pulley quite easily and I have triple checked that the timing marks still line up top and bottom and as I used the proper locking tools I am happy that everything has come apart and gone back together fine. I can also lock and unlock the car on the remote so there is still enough juice in the battery to activate the central locking and alarm so I would have thought the immobiliser would activate and deactivate as well.

I don't have access to VAGCOM so I'm not sure what I can try next. Can anyone help?
It is definitely your battery, mine did the same thing with the needle going mad (freaked me out thought something was seriously wrong when i saw that!). Put the battery on a full charge overnight, if it still doesnt work buy a new battery!

Your central locking etc will still work as they use hardly any power to use. My car wouldnt start with a jumpstart either - charged the battery overnight and it started 1st time in the morning!
 

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well it really depends how beefy your jump leads are...I have a set that are big heavy duty ones and they will start anything that is stone dead from my battery with engine running[:O]
 

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If The battery is Dead Flat (No Voltage) and you connect a pair of Jump leads to another vehicle, the jump leads need to be of a heavy duty garage type (as in the ones madman has) so they can provide enough currant, which on initial start on a avg Diesel is 400a + otherwise you will indeed have to run the engine of the slave vehicle a short while to put some reserve into the flat battery.

Always a good idea if you have the time to let the flat battery see some voltage from the slave vehicle, to avoid pulling the guts out of the other battery and the alternator .

always worked for me in the trade for 30yrs
 

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Discussion Starter · #12 ·
Hi Guys, some wise words with regard to the flat battery. The jump leads I tried are not that meaty and I didn't leave the jump vehicle connected for a while before trying to start my Bora so I guess the flat battery would act as a voltage sink to begin with.

The battery is out of the car now and being charged so I will try again tomorrow. I'll let you know how I get on.

Thanks for all your replies.
 

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If The battery is Dead Flat (No Voltage) and you connect a pair of Jump leads to another vehicle, the jump leads need to be of a heavy duty garage type (as in the ones madman has) so they can provide enough currant, which on initial start on a avg Diesel is 400a + otherwise you will indeed have to run the engine of the slave vehicle a short while to put some reserve into the flat battery.

Always a good idea if you have the time to let the flat battery see some voltage from the slave vehicle, to avoid pulling the guts out of the other battery and the alternator .

always worked for me in the trade for 30yrs
Sorry i assumed hed left it on for a while to charge the battery a bit as i knew this was common practise. When i had the problem i was trying to jumpstart with a starter pack. Was just letting him know it was the battery
 

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Discussion Starter · #14 ·
Battery fully charged and the car started first time no problem just as many of you said it would. I've jump started many cars in my time but never seen a car not even attempt to turn the engine over. You live and learn.

I took the car for a test run and I still have the same problem as before I changed the water pump and cam belt, the heater keeps blowing hot and cold. I also changed the thermostat at the same time and I have just noticed that after an hour of running the engine the hose from the bottom of the radiator to the thermostat housing in the block is stone cold, not even luke warm. The top hose out of the block to the top of the rad is almost melting, do you think I could have a blocked radiator?
 

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Battery fully charged and the car started first time no problem just as many of you said it would. I've jump started many cars in my time but never seen a car not even attempt to turn the engine over. You live and learn.

I took the car for a test run and I still have the same problem as before I changed the water pump and cam belt, the heater keeps blowing hot and cold. I also changed the thermostat at the same time and I have just noticed that after an hour of running the engine the hose from the bottom of the radiator to the thermostat housing in the block is stone cold, not even luke warm. The top hose out of the block to the top of the rad is almost melting, do you think I could have a blocked radiator?
Worth a check. Take it off and flush it through. If your water pump actually went, did you check the head gasket?
 

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Discussion Starter · #16 ·
Worth a check. Take it off and flush it through. If your water pump actually went, did you check the head gasket?
That is next on the list but I will take a look at the radiator first.
 

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Battery fully charged and the car started first time no problem just as many of you said it would. I've jump started many cars in my time but never seen a car not even attempt to turn the engine over. You live and learn.

I took the car for a test run and I still have the same problem as before I changed the water pump and cam belt, the heater keeps blowing hot and cold. I also changed the thermostat at the same time and I have just noticed that after an hour of running the engine the hose from the bottom of the radiator to the thermostat housing in the block is stone cold, not even luke warm. The top hose out of the block to the top of the rad is almost melting, do you think I could have a blocked radiator?
Glad it started after the re charge mate
 
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