c1242 abs code need help
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From: Dyer, IN
http://www.flickr.com/photos/1545929...50237/sizes/l/
I highlighted on the above diagram what is known, and what is not. The mystery pin I circled needs to be known to measure the resistance through the motor.
All we are doing is trying to isolate the EBCM from the PUMP. Without a tech 2, you can't command on the pump, which in turn...does two things:
1) Makes sure the control circuit is working in the EBCM
2) Makes sure the pump is functioning.
I highlighted on the above diagram what is known, and what is not. The mystery pin I circled needs to be known to measure the resistance through the motor.
All we are doing is trying to isolate the EBCM from the PUMP. Without a tech 2, you can't command on the pump, which in turn...does two things:
1) Makes sure the control circuit is working in the EBCM
2) Makes sure the pump is functioning.
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Racer
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From: baton rouge louisiana
so bill can you add to this,,,,it seems like nobody knows where the voltage comes from powering the pump,,please read back and tell me what you think i can test furthure to prove my trouble
Tech Contributor
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From: Charlotte, NC (formerly Endicott, NY)
Bill
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Racer
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From: baton rouge louisiana
bill
there is a plug right underneath the other large plug and it has two black wires,if this is the pump motor winding im looking at i see 18k olms and do i understand you?you want me to plug it back in stick the wire with a test light and ground the other side and have someone start the car and i should see voltage steady or for just a few seconds?thanks tony
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Racer
Joined: Sep 2008
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From: baton rouge louisiana
bill
i think i found a problem,,,if that two wire plug right inder the big conector is the pump motor winding,,i read 100 olms one side to ground on the terminal ,,,,does this mean my winding is bad grounded to the case?
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Tech Contributor
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From: Charlotte, NC (formerly Endicott, NY)
3
- Disconnect the pump motor harness pigtail connector of the BPMV.
- Measure the resistance between each pump motor control circuit and the housing of the BPMV at the pump motor harness pigtail connector of the BPMV.
Over Limit
Go to Step 5
Go to Step 4
4
Replace the EBCM and the BPMV. Refer to Electronic Brake Control Module (EBCM) Replacement and Brake Pressure Modulator Valve (BPMV) Replacement .
Did you complete the repair?
--
Go to Step 6
--
Since you are reading 100 ohms that would indicate the BPMV should have been replaced at the same time you did the EBCM repair. A high resistance short to ground in the motor circuit would increase current through the system relay and possibly burn the relay contacts or cause an open circuit within the EBCM between the relay and the BPMV.
Bill
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From: baton rouge louisiana
From the diagnostic for C1214 Step 3:
3
Over Limit
Go to Step 5
Go to Step 4
4
Replace the EBCM and the BPMV. Refer to Electronic Brake Control Module (EBCM) Replacement and Brake Pressure Modulator Valve (BPMV) Replacement .
Did you complete the repair?
--
Go to Step 6
--
Since you are reading 100 ohms that would indicate the BPMV should have been replaced at the same time you did the EBCM repair. A high resistance short to ground in the motor circuit would increase current through the system relay and possibly burn the relay contacts or cause an open circuit within the EBCM between the relay and the BPMV.
Bill
3
- Disconnect the pump motor harness pigtail connector of the BPMV.
- Measure the resistance between each pump motor control circuit and the housing of the BPMV at the pump motor harness pigtail connector of the BPMV.
Over Limit
Go to Step 5
Go to Step 4
4
Replace the EBCM and the BPMV. Refer to Electronic Brake Control Module (EBCM) Replacement and Brake Pressure Modulator Valve (BPMV) Replacement .
Did you complete the repair?
--
Go to Step 6
--
Since you are reading 100 ohms that would indicate the BPMV should have been replaced at the same time you did the EBCM repair. A high resistance short to ground in the motor circuit would increase current through the system relay and possibly burn the relay contacts or cause an open circuit within the EBCM between the relay and the BPMV.
Bill
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Racer
Joined: Sep 2008
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From: baton rouge louisiana
?
do you have a picture of the pigtail?is tihs two wire connector the one for the motor ? Disconnect the pump motor harness pigtail connector of the BPMV.the two wire connector im talking about is on the ebcm not the bpmv,,there is a three wire connector on the bpmv do you think the wire harness on the right here is the one? http://www.bustedcar.com/EBCM_001.jpg look at this???? they say three wires http://www.bustedcar.com/our_pictures1.htm if this is talking about the three wire connector on the bpmv then its good ,no grounds reaDisconnect the pump motor harness pigtail connector of the BPMV.
Measure the resistance between each pump motor control circuit and the housing of the BPMV at the pump motor harness pigtail connector of the BPMV.
d
Measure the resistance between each pump motor control circuit and the housing of the BPMV at the pump motor harness pigtail connector of the BPMV.
d
Last edited by tonycorvettes; Dec 3, 2008 at 08:45 PM.
Thread Starter
Racer
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Posts: 461
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From: baton rouge louisiana
Since you are reading 100 ohms that would indicate the BPMV should have been replaced at the same time you did the EBCM repair. A high resistance short to ground in the motor circuit would increase current through the system relay and possibly burn the relay contacts or cause an open circuit within the EBCM between the relay and the BPMV.
i was looking at the internal connector seeing these grounds,maybe they belong there,looking the other way on the wire pigtail that looks like it goes to the other side where the pump is,that direstion is clean
i was looking at the internal connector seeing these grounds,maybe they belong there,looking the other way on the wire pigtail that looks like it goes to the other side where the pump is,that direstion is clean
Tech Contributor
Joined: Oct 1999
Posts: 40,995
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From: Charlotte, NC (formerly Endicott, NY)
You can just do a to the top post. I do not have any pictures of the unit and my car isn't where I can get to it for several days. If the two wire harness is the only one coming out of the BPMV it should by elimination be the one that goes to the motor. The schematic only shows two wires coming out of the BPMV.
Bill
Bill
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ok,,,making progress
the two wires ,i have been talking about are the pump motor,,,,i opened the connector up and put 12v bat and grd on them and the pump runs ,,,,,,,,now when i look the other direction from the connector from the ebcm i have the wife start the car and i see 12v on one side but i dont see a grd on the other just some battery ,,,what do you think about that? does your information show i should get a ground from where ?maybe its the ebcm i just got back from absfixers thats bad,go figure?
Last edited by tonycorvettes; Dec 3, 2008 at 11:44 PM.
Tech Contributor
Joined: Oct 1999
Posts: 40,995
Likes: 9,759
From: Charlotte, NC (formerly Endicott, NY)
the two wires ,i have been talking about are the pump motor,,,,i opened the connector up and put 12v bat and grd on them and the pump runs ,,,,,,,,now when i look the other direction from the connector from the ebcm i have the wife start the car and i see 12v on one side but i dont see a grd on the other just some battery ,,,what do you think about that? does your information show i should get a ground from where ?maybe its the ebcm i just got back from absfixers thats bad,go figure?
I will be traveling the next 4 days and will be back Monday.
Bill
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From: baton rouge louisiana
im back
ok,i told you wrong on the reading of step 3 bill,sorry,,,3
Disconnect the pump motor harness pigtail connector of the BPMV.
Measure the resistance between each pump motor control circuit and the housing of the BPMV at the pump motor harness pigtail connector of the BPMV.
Does the DMM display the specified value?
Over Limit
Go to Step 5
Go to Step 4
i get no resistNCE reading at all ,LIKE AN OPEN,reading the two wires to the motor to the housing,i would think thats what i should get,,and i put 12 volts on the motor,it runs great,,so what step 4 and 5 whats next ,what do you think bill or mike or anyone else thanks tony
Disconnect the pump motor harness pigtail connector of the BPMV.
Measure the resistance between each pump motor control circuit and the housing of the BPMV at the pump motor harness pigtail connector of the BPMV.
Does the DMM display the specified value?
Over Limit
Go to Step 5
Go to Step 4
i get no resistNCE reading at all ,LIKE AN OPEN,reading the two wires to the motor to the housing,i would think thats what i should get,,and i put 12 volts on the motor,it runs great,,so what step 4 and 5 whats next ,what do you think bill or mike or anyone else thanks tony
