c1242 abs code need help
Thread Starter
Racer
Joined: Sep 2008
Posts: 461
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From: baton rouge louisiana
c1242 abs code need help
Using J 39200 DMM, measure resistance between BPMV internal connector terminal 8 and motor ground stud.
is what this is saying is to unplug the big connector on the ebcm set it aside and touch pin 8 inside the internal connector and read with an olm meter one side to grd and you should read about 8000 olhms or less?
is what this is saying is to unplug the big connector on the ebcm set it aside and touch pin 8 inside the internal connector and read with an olm meter one side to grd and you should read about 8000 olhms or less?
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Using J 39200 DMM, measure resistance between BPMV internal connector terminal 8 and motor ground stud.
is what this is saying is to unplug the big connector on the ebcm set it aside and touch pin 8 inside the internal connector and read with an olm meter one side to grd and you should read about 8000 olhms or less?
is what this is saying is to unplug the big connector on the ebcm set it aside and touch pin 8 inside the internal connector and read with an olm meter one side to grd and you should read about 8000 olhms or less?
Tech Contributor
Joined: Jan 2007
Posts: 19,245
Likes: 1,091
From: Dyer, IN
Here's why the procedure you are using won't work. On a 2000(or earlier) the ground is a hard ground(not switched). So using this procedure, you are reading through the motor to see if it has opened up.
http://www.flickr.com/photos/1545929...30000/sizes/l/
On a 2001, the ground for the pump motor is switched; thus, you cannot read through the motor the way you are doing it, unless the pump motor control switch is closed.
http://www.flickr.com/photos/1545929...96359/sizes/l/
http://www.flickr.com/photos/1545929...30000/sizes/l/
On a 2001, the ground for the pump motor is switched; thus, you cannot read through the motor the way you are doing it, unless the pump motor control switch is closed.
http://www.flickr.com/photos/1545929...96359/sizes/l/
Thread Starter
Racer
Joined: Sep 2008
Posts: 461
Likes: 11
From: baton rouge louisiana
im so confuseddddddddddddddddddddd
this is a 2001 ....bottom line is i had my ebcm tested by absfixers put it back ,now im getting only a 1242 code,,would you think my pump is bad?how can i test it ?or what else can i check short of having a teck 11 ?i checked the ground points ans fuse 52 and i have a permanent grd on the pigtail at g with it unpluges ,l ,,,,and 12v on a of the terminal strip do ,,looking into the ebcm g and a i seee nothing no potential,,,one funny thing i have noticed is this,,when i unscrew the nut on the ground lug on the lh rail it has a connector with 4 black wires and one solo blk wire with an eyelet,,when i ground one side of my vom meter and put the other side on the 4 blk wires i see a ground looking toward the harness why?is this ok,,i opened them u and found that one of the wires has a permanent ground,this seems funny to me,,if it needs a ground from the lh rail ,why does it have a grd already?nalrc
Last edited by tonycorvettes; Dec 3, 2008 at 12:34 PM.
Tech Contributor
Joined: Jan 2007
Posts: 19,245
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From: Dyer, IN
Tech Contributor
Joined: Jan 2007
Posts: 19,245
Likes: 1,091
From: Dyer, IN
this is a 2001 ....bottom line is i had my ebcm tested by absfixers put it back ,now im getting only a 1242 code,,would you think my pump is bad?how can i test it ?or what else can i check short of having a teck 11 ?i checked the ground points ans fuse 52 and i have a permanent grd on the pigtail at g with it unpluges ,l ,,,,and 12v on a of the terminal strip do ,,looking into the ebcm g and a i seee nothing no potential,,,one funny thing i have noticed is this,,when i unscrew the nut on the ground lug on the lh rail it has a connector with 4 black wires and one solo blk wire with an eyelet,,when i ground one side of my vom meter and put the other side on the 4 blk wires i see a ground looking toward the harness why?is this ok,,i opened them u and found that one of the wires has a permanent ground,this seems funny to me,,if it needs a ground from the lh rail ,why does it have a grd already?nalrc
Look at the diagram for the 2001 EBCM. Notice that at Pin G, the ground for the pump is supplied via a switch(pump motor control inside the EBCM). If this switch is not closed, you will read an open(or no voltage). Additionally, if the switched battery system voltage has not actuated, then 12 volts will not be applied to the pump. This is why a tech 2 is required to manually activate the pump. Finally, the harness side of the connector should always have a ground on pins G and F.
What is the resistance value of the grounds measured at G and F?
Also, have you checked fuse #5?
Last edited by lucky131969; Dec 3, 2008 at 01:30 PM.
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With the EBCM in your hand you should get an open circuit if you measure through Pin G. Pin G connects the ground wire from G103 (the lug you found attached to the frame along with the splice pack) to the internal ground switch in the EBCM. The other side of that switch comes out of the EBCM and goes to the BPMV but the pin number isn't defined in the schematic. You may be able to determine it when you have everything in front of you. If you measure this circuit through the BPMV you should see a low resistance (discussed previously).
However, you will be probably be better off following the diagnostic for your year car that I posted in the other thread.
Several of us are saying the same thing. You need to listen.
Bill
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From: Dyer, IN
This is what I told you in my PM yesterday. Based on the updated circuitry the C1242 code doesn't imply an open BPMV ground circuit as it did previously. That is why you need to follow the diagnostic for the year car you have. The code lists posted on the internet can be very misleading.
With the EBCM in your hand you should get an open circuit if you measure through Pin G. Pin G connects the ground wire from G103 (the lug you found attached to the frame along with the splice pack) to the internal ground switch in the EBCM. The other side of that switch comes out of the EBCM and goes to the BPMV but the pin number isn't defined in the schematic. You may be able to determine it when you have everything in front of you. If you measure this circuit through the BPMV you should see a low resistance (discussed previously).
However, you will be probably be better off following the diagnostic for your year car that I posted in the other thread.
Several of us are saying the same thing. You need to listen.
Bill
With the EBCM in your hand you should get an open circuit if you measure through Pin G. Pin G connects the ground wire from G103 (the lug you found attached to the frame along with the splice pack) to the internal ground switch in the EBCM. The other side of that switch comes out of the EBCM and goes to the BPMV but the pin number isn't defined in the schematic. You may be able to determine it when you have everything in front of you. If you measure this circuit through the BPMV you should see a low resistance (discussed previously).
However, you will be probably be better off following the diagnostic for your year car that I posted in the other thread.
Several of us are saying the same thing. You need to listen.
Bill
Sorry Bill, I didn't realize there were numerous posts.
Tech Contributor
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From: Dyer, IN
No biggie, but now you have me curious. Does your 2002 wiring diagram look different than this?
http://www.flickr.com/photos/1545929...46747/sizes/l/
I don't see the connection from G101 to G102.
http://www.flickr.com/photos/1545929...46747/sizes/l/
I don't see the connection from G101 to G102.
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Thread Starter
Racer
Joined: Sep 2008
Posts: 461
Likes: 11
From: baton rouge louisiana
Thread Starter
Racer
Joined: Sep 2008
Posts: 461
Likes: 11
From: baton rouge louisiana
ok
fuse 5 is good,,and im getting a solid ground at f and g ,,,and 12 v at a at the harnes connector ,,,and i do see an open condition looking into the unit itself on f ,some people are telling me grnd c101 and some 103 ? all i know its the one by the pump on the left lise rail ,,,,,,,,,,,,,,,,,,what next please
Last edited by tonycorvettes; Dec 3, 2008 at 04:17 PM.
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Joined: Jan 2007
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From: Dyer, IN
fuse 5 is good,,and im getting a solid ground at f and g ,,,and 12 v at a at the harnes connector ,,,and i do see an open condition looking into the unit itself on f ,some people are telling me grnd c101 and some 103 ? all i know its the one by the pump on the left lise rail ,,,,,,,,,,,,,,,,,,what next please
Also, like Bill already stated, the specific pin for the 12 volt input is not identified on the schematic. If you can ascertain which pin that is by visual inspection, you can take a resistance reading through the motor.
Last edited by lucky131969; Dec 3, 2008 at 04:23 PM.
Thread Starter
Racer
Joined: Sep 2008
Posts: 461
Likes: 11
From: baton rouge louisiana
dont understand
explain what you want me to read,,looking into the internal connection?or are you asking me to find another 12v from the harness connector? should i do this? Using J 39200 DMM, measure resistance between BPMV internal connector terminal 8 and motor ground stud
Last edited by tonycorvettes; Dec 3, 2008 at 04:37 PM.
Tech Contributor
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From: Dyer, IN