Changed the CPS, now car won't start at all
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MBWorld Fanatic!
Joined: Jul 2006
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From: Central Florida
R129, XF Sportbrake, SC400
Changed the CPS, now car won't start at all
I changed the CPS today and now the car won't crank at all. No attempt to start. I don't think that the CPS can be put in incorrectly and I did plug it back in. I tried to jump start it and still nothing. I don't know if there's a wire that could have slipped out somewhere in the process? I looked everywhere and found nothing.
Thread Starter
MBWorld Fanatic!
Joined: Jul 2006
Posts: 2,147
Likes: 2
From: Central Florida
R129, XF Sportbrake, SC400
Thread Starter
MBWorld Fanatic!
Joined: Jul 2006
Posts: 2,147
Likes: 2
From: Central Florida
R129, XF Sportbrake, SC400
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MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
12.7V = 100%
12.45V =75%
12.24V = 50%
12.06V = 25%
11.89V = 0%
If there is no "click" when you turn the key to start position then you're probably not getting juice to the starter assuming that start circuit was OK before you replaced the CPS. Why did you replace the CPS? If no click then check fuses and relays.
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Thread Starter
MBWorld Fanatic!
Joined: Jul 2006
Posts: 2,147
Likes: 2
From: Central Florida
R129, XF Sportbrake, SC400
Correct. The starter takes the most juice so just because the lights are on doesn't mean the battery is OK. First make sure terminals are clean and tight. Measure battery voltage for charge state:
12.7V = 100%
12.45V =75%
12.24V = 50%
12.06V = 25%
11.89V = 0%
If there is no "click" when you turn the key to start position then you're probably not getting juice to the starter assuming that start circuit was OK before you replaced the CPS. Why did you replace the CPS? If no click then check fuses and relays.
12.7V = 100%
12.45V =75%
12.24V = 50%
12.06V = 25%
11.89V = 0%
If there is no "click" when you turn the key to start position then you're probably not getting juice to the starter assuming that start circuit was OK before you replaced the CPS. Why did you replace the CPS? If no click then check fuses and relays.
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
Oops, I missed that part of it. Look at the fuses and consider the relay. I'm guessing (you probably are too) that you knocked of a wire or shorted something while putting in the CPS but I can't think what's in that area that would do that. Did you drop anything and not find it?
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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
Check everything you have recently disturbed. Be very careful jump starting these cars - you can blow a SAM
Check Fuses 31, 52 & 57
The starter relay is in cavity "S" in the front SAM.
Good luck!
Check Fuses 31, 52 & 57
The starter relay is in cavity "S" in the front SAM.
Good luck!
Thread Starter
MBWorld Fanatic!
Joined: Jul 2006
Posts: 2,147
Likes: 2
From: Central Florida
R129, XF Sportbrake, SC400
Okay, fuse 52 was blown. Now the car cranks but never "catches", same problem as before. This time there's a new CPS. I could not see fuse 57. What is it for?
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
Newbie
Joined: Apr 2008
Posts: 1
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Mercedes Benz c320 2002
Can you tell me if you did anything to fix this???. I have the same problem. My car would crank but won't turn on. Has been doing this for 5 days now, Cranks but won't turn on, if I try like 20 times it will eventually turn on. I also got another problem now when I drive and stop at a red light for a long time it will turn off, I'm wording if this is because I have been leaving the car on when I have been putting gas to it?.. Please help me fix this issue to my car.
