Starting Problems
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C270CDI
Starting Problems
Have a C270CDI 10yr old. Lately is very erratic on starting. On switch-on the indicators for the gearbox shift setting (W/S) and the gear position fail to appear and there is no attempt to actually start. There are various other indicators which do not appear to be correct (airbag check for ex.). Trying it a few (or more) times and it may eventually start. 
Thoughts are heading to either wiring or CPU problems. Anyone out there have experience or suggestion?
Thoughts are heading to either wiring or CPU problems. Anyone out there have experience or suggestion?
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Look at all the starting problem threads recently posted.
In your case it might be the EIS but check everything else first. Also put your foot on the brake & move the shifter backwards & forwards a few times to make sure it is not the interlock switch. Remember it will only start in P or N.
In your case it might be the EIS but check everything else first. Also put your foot on the brake & move the shifter backwards & forwards a few times to make sure it is not the interlock switch. Remember it will only start in P or N.
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C270CDI
Have tried everything - releasing the shift and then back to P and still failed to start. Then doing absolutely nothing except turning the key a number a times before it may start - each time it fails it is also a case that the gearbox position indicator on the dash shows nothing (not even P) and then when I turn the key and the P is shown the engine will fire. My feeling is that either there are random failures of some signals to the control unit OR the software/control unit is not dealing with all the checks correctly. I have to say that I am doubtful that it is a wiring problem as, although the car is 10 years old, it has only done 48k miles and any wiring accessed is in good nick.
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Does the car always crank over? Are you always able to turn the key?
If the car always cranks over then being a diesel one would more inclined to believe that the cause is electronic & your dash lights would tend to confirm this.
At your mileage there is no reason to suspect the injection system. When the car does start does it run normally? Can you hear the electric primary feed pump running under the back seat?
That's why unless it's a loose connection somewhere ~ or a failed start enable sensor ~ or no fuel pressure, I suspect the EIS (electronic ignition switch) might be the problem.
Otherwise all you need is fuel, air & crankover to start a diesel.
If the car always cranks over then being a diesel one would more inclined to believe that the cause is electronic & your dash lights would tend to confirm this.
At your mileage there is no reason to suspect the injection system. When the car does start does it run normally? Can you hear the electric primary feed pump running under the back seat?
That's why unless it's a loose connection somewhere ~ or a failed start enable sensor ~ or no fuel pressure, I suspect the EIS (electronic ignition switch) might be the problem.
Otherwise all you need is fuel, air & crankover to start a diesel.
Thread Starter
Newbie
Joined: Aug 2012
Posts: 4
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C270CDI
Does the car always crank over? Are you always able to turn the key?
If the car always cranks over then being a diesel one would more inclined to believe that the cause is electronic & your dash lights would tend to confirm this.
At your mileage there is no reason to suspect the injection system. When the car does start does it run normally? Can you hear the electric primary feed pump running under the back seat?
That's why unless it's a loose connection somewhere ~ or a failed start enable sensor ~ or no fuel pressure, I suspect the EIS (electronic ignition switch) might be the problem.
Otherwise all you need is fuel, air & crankover to start a diesel.
If the car always cranks over then being a diesel one would more inclined to believe that the cause is electronic & your dash lights would tend to confirm this.
At your mileage there is no reason to suspect the injection system. When the car does start does it run normally? Can you hear the electric primary feed pump running under the back seat?
That's why unless it's a loose connection somewhere ~ or a failed start enable sensor ~ or no fuel pressure, I suspect the EIS (electronic ignition switch) might be the problem.
Otherwise all you need is fuel, air & crankover to start a diesel.
- yes to the first (perfectly!)and not sure to the second.
- any easy way to rule out the EIS?
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
OK - If it does not crank chack fuse 52 for corrosion & make sure it is 20 amp & not 15 as originally specified. Check the starter relay.
Have the EIS checked with a Star DAS.
Have the EIS checked with a Star DAS.
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Super Moderator
Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
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