04-05-2023, 09:52 AM
|
#1
|
Registered User
Join Date: Apr 2021
Location: MD
Posts: 22
|
Thanks for the quick feedback!
CPS: Though it's brand new (Pelican) and no sign of not working (tests alright), I will get another new one to be absolutely sure it's not that.
Immobilizer: Car was in garage for past 3 years so can exclude that it got wet. Also: would the immobilizer not prevent the engine from cranking in the first place?
Will check the relays in the back.
|
|
|
04-05-2023, 10:45 AM
|
#2
|
Registered User
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 6,614
|
Quote:
Originally Posted by Kice
Thanks for the quick feedback!
CPS: Though it's brand new (Pelican) and no sign of not working (tests alright), I will get another new one to be absolutely sure it's not that.
Immobilizer: Car was in garage for past 3 years so can exclude that it got wet. Also: would the immobilizer not prevent the engine from cranking in the first place?
Will check the relays in the back.
|
Long before aimlessly throwing parts at it, why not check and see if the DME is getting a signal from the CPS? Trace the CPS wires to the connector at the DME and look for a low voltage signal on them at the DME end when the engine is turning over; if you have a signal, it isn't the CPS.
__________________
“Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
|
|
|
04-05-2023, 12:23 PM
|
#3
|
Registered User
Join Date: Apr 2021
Location: MD
Posts: 22
|
Quote:
Originally Posted by JFP in PA
Long before aimlessly throwing parts at it, why not check and see if the DME is getting a signal from the CPS? Trace the CPS wires to the connector at the DME and look for a low voltage signal on them at the DME end when the engine is turning over; if you have a signal, it isn't the CPS.
|
Thanks! Is there a chart for the pins in the DME plug? Or is it best to go by the color coded cables from the CPS?
|
|
|
04-05-2023, 12:39 PM
|
#4
|
Registered User
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 6,614
|
Quote:
Originally Posted by Kice
Thanks! Is there a chart for the pins in the DME plug? Or is it best to go by the color coded cables from the CPS?
|
Service manuals will have a complete wiring diagram.
__________________
“Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
|
|
|
04-05-2023, 02:27 PM
|
#5
|
Motorist & Coffee Drinker
Join Date: Jul 2014
Location: Oklahoma
Posts: 3,932
|
Quote:
Originally Posted by Kice
Thanks! Is there a chart for the pins in the DME plug? Or is it best to go by the color coded cables from the CPS?
|
Maybe pin 78..?
I have a link to this in my folder of DME stuff, Says it's DME 5.2.2: https://www.renntech.org/topic/28597-porsche-996-dme-pinouts-and-connectors/
__________________
I am not an attorney, mechanic, or member of the clergy. Following any advice given in my posts is done at your own peril.
|
|
|
04-07-2023, 03:47 PM
|
#6
|
Registered User
Join Date: Apr 2021
Location: MD
Posts: 22
|
Thanks. I checked the relays in the trunk per Bentley manual and they all seem ok.
I also measured the voltage directly from the CPS connector when cranking the engine and it clearly produces a signal. So the CPS seems to be fine.
I am however unclear how to check if that signal reaches the DM, because when I disconnect the DME connector to check for the signal on the respective pins the car will not start at all. I guess need to jumper the starter for that test?
|
|
|
04-07-2023, 04:07 PM
|
#7
|
Registered User
Join Date: Aug 2018
Location: Woodland Wa
Posts: 1,309
|
Quote:
Originally Posted by Kice
Thanks. I checked the relays in the trunk per Bentley manual and they all seem ok.
I also measured the voltage directly from the CPS connector when cranking the engine and it clearly produces a signal. So the CPS seems to be fine.
I am however unclear how to check if that signal reaches the DM, because when I disconnect the DME connector to check for the signal on the respective pins the car will not start at all. I guess need to jumper the starter for that test?
|
Use a Multi Meter to check continuity and for short to ground on the respective pins
|
|
|
04-07-2023, 05:17 PM
|
#8
|
Registered User
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 6,614
|
Quote:
Originally Posted by Kice
Thanks. I checked the relays in the trunk per Bentley manual and they all seem ok.
I also measured the voltage directly from the CPS connector when cranking the engine and it clearly produces a signal. So the CPS seems to be fine.
I am however unclear how to check if that signal reaches the DM, because when I disconnect the DME connector to check for the signal on the respective pins the car will not start at all. I guess need to jumper the starter for that test?
|
No, the CPS is a Hall Effect sensor, it only has to turn over to generate a signal, it does not need to run.
__________________
“Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
|
|
|
04-07-2023, 05:43 PM
|
#9
|
Registered User
Join Date: Apr 2021
Location: MD
Posts: 22
|
Quote:
Originally Posted by JFP in PA
No, the CPS is a Hall Effect sensor, it only has to turn over to generate a signal, it does not need to run.
|
Understood, but how do i get the flywheel to turn with the DME (and hence the starter) disconnected so i have access to the DME connector pins?
|
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is On
|
|
|
All times are GMT -8. The time now is 01:42 PM.
| |