S420 won't start
Thread Starter
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Joined: Dec 2004
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From: Hawaii
05 SLK 350, 97 S420, 92 Jeep, 04 Kia, 28 Ford Tudor, 51 Ford F3, 01 Harley, 03 Harley
S420 won't start
My 97 S420 won't start. Good battery, good turn over, good spark. Appears fuel delivery is the problem but not sure where to check.
Note: Checked fuses and all good (in engine compartment and in trunk).
Suspect fuel oil pump but not sure where to check.
Note: Checked fuses and all good (in engine compartment and in trunk).
Suspect fuel oil pump but not sure where to check.
Thread Starter
Member
Joined: Dec 2004
Posts: 132
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From: Hawaii
05 SLK 350, 97 S420, 92 Jeep, 04 Kia, 28 Ford Tudor, 51 Ford F3, 01 Harley, 03 Harley
All of a sudden, drove it two days before and no problem. The car is in excellent condition and well maintained so I am thinking a relay or pump failure. Will tackle it today.
Thread Starter
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Joined: Dec 2004
Posts: 132
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From: Hawaii
05 SLK 350, 97 S420, 92 Jeep, 04 Kia, 28 Ford Tudor, 51 Ford F3, 01 Harley, 03 Harley
I checked the fuel pump and it does not start when the ignition is turned on. I checked the plug to the pump and there is no voltage reading either.
I pulled out the relay and tested it. Put 12V to the two terminals and it pulled in the relay so that appears ok.
I am trying to trace further back and see what sends the signal to the relay.
I thought of hooking up a battery to the fuel pump and testing it but with no power to the connection plug I believe it is another modual or relay up the line.
I pulled out the relay and tested it. Put 12V to the two terminals and it pulled in the relay so that appears ok.
I am trying to trace further back and see what sends the signal to the relay.
I thought of hooking up a battery to the fuel pump and testing it but with no power to the connection plug I believe it is another modual or relay up the line.
Thread Starter
Member
Joined: Dec 2004
Posts: 132
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From: Hawaii
05 SLK 350, 97 S420, 92 Jeep, 04 Kia, 28 Ford Tudor, 51 Ford F3, 01 Harley, 03 Harley
Yep, fuse is good, and pump works when I use an external battery to test it. I am towing it in. Frustrated with all the electronics!!
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But most CPS's fail gradually producing cold starts followed by hot no-starts. I was just gathering clues in order to try to help OP.
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03 E500 and Corvette
So this could still be the CPS failure as even if the engine is turning over a failed CPS would give no voltage to the pump and the engine will not start due to fuel turned off AND no spark.
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From: Hawaii
05 SLK 350, 97 S420, 92 Jeep, 04 Kia, 28 Ford Tudor, 51 Ford F3, 01 Harley, 03 Harley
Took it in and got a call back. For some reason the security system shutdown the signal to the pump.
What is confusing is the digital key has not worked for some time (I kept putting off fixing it) and doesn't have a battery in it.
The key has been used to open/lock the car and normal use. I am taking the valet key to the tech tomorrow to see if that has something to do with the alarm system. I doubt it but will find out. Ah, my '28 will for sure out last this, and the other newer, cars.
What is confusing is the digital key has not worked for some time (I kept putting off fixing it) and doesn't have a battery in it.
The key has been used to open/lock the car and normal use. I am taking the valet key to the tech tomorrow to see if that has something to do with the alarm system. I doubt it but will find out. Ah, my '28 will for sure out last this, and the other newer, cars.
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From: Louisiana
03 E500 and Corvette
Took it in and got a call back. For some reason the security system shutdown the signal to the pump.
What is confusing is the digital key has not worked for some time (I kept putting off fixing it) and doesn't have a battery in it.
The key has been used to open/lock the car and normal use. I am taking the valet key to the tech tomorrow to see if that has something to do with the alarm system. I doubt it but will find out. Ah, my '28 will for sure out last this, and the other newer, cars.
What is confusing is the digital key has not worked for some time (I kept putting off fixing it) and doesn't have a battery in it.
The key has been used to open/lock the car and normal use. I am taking the valet key to the tech tomorrow to see if that has something to do with the alarm system. I doubt it but will find out. Ah, my '28 will for sure out last this, and the other newer, cars.
Breaker points don't have a security key.
Thread Starter
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Joined: Dec 2004
Posts: 132
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From: Hawaii
05 SLK 350, 97 S420, 92 Jeep, 04 Kia, 28 Ford Tudor, 51 Ford F3, 01 Harley, 03 Harley
Darndest thing. The regular, valet, key was put in the ignition and the engine started right up!
On the computer with the remote key in it shows all fine EXCEPT engine start was not permitted....
I am not an electronic wizard and I did not see this on any electrical drawings but only thing we figured out the key may be worn down some and there must be a pin/switch in the ignition switch that this key will not activate. Where as the other key, seldom used, triggered this contact/switch/sensor or what ever device tells the computer system to allow start up.
Thanks for the comments, checks and answers....
Makes you wonder if a car company just made a simple car, minimum extras (maybe radio and lights, ok throw in electric windows) it would probably sell and may last!
On the computer with the remote key in it shows all fine EXCEPT engine start was not permitted....
I am not an electronic wizard and I did not see this on any electrical drawings but only thing we figured out the key may be worn down some and there must be a pin/switch in the ignition switch that this key will not activate. Where as the other key, seldom used, triggered this contact/switch/sensor or what ever device tells the computer system to allow start up.
Thanks for the comments, checks and answers....
Makes you wonder if a car company just made a simple car, minimum extras (maybe radio and lights, ok throw in electric windows) it would probably sell and may last!
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Joined: Mar 2006
Posts: 3,254
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From: Louisiana
03 E500 and Corvette
Darndest thing. The regular, valet, key was put in the ignition and the engine started right up!
On the computer with the remote key in it shows all fine EXCEPT engine start was not permitted....
I am not an electronic wizard and I did not see this on any electrical drawings but only thing we figured out the key may be worn down some and there must be a pin/switch in the ignition switch that this key will not activate. Where as the other key, seldom used, triggered this contact/switch/sensor or what ever device tells the computer system to allow start up.
Thanks for the comments, checks and answers....
Makes you wonder if a car company just made a simple car, minimum extras (maybe radio and lights, ok throw in electric windows) it would probably sell and may last!
On the computer with the remote key in it shows all fine EXCEPT engine start was not permitted....
I am not an electronic wizard and I did not see this on any electrical drawings but only thing we figured out the key may be worn down some and there must be a pin/switch in the ignition switch that this key will not activate. Where as the other key, seldom used, triggered this contact/switch/sensor or what ever device tells the computer system to allow start up.
Thanks for the comments, checks and answers....
Makes you wonder if a car company just made a simple car, minimum extras (maybe radio and lights, ok throw in electric windows) it would probably sell and may last!
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