EBCM changed, more codes...
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EBCM changed, more codes...
does anyone have any ideas about this... i was getting a c1255 code, i removed & cleaned all connections (no help). so i installed a new ebcm on my 1999 and a bunch of new codes popped up...
c1247 - brake pressure differential switch activated
c1271&72 - ebcm internal solenoid circuit
c1282 - yaw rate sensor bias circuit malfunction
c1285 - lateral accelerometer circuit
c1296 - master cylinder pressure sensor circuit
all of these codes are current. will a scan tool get ride of these for good? thanks for any help!!
c1247 - brake pressure differential switch activated
c1271&72 - ebcm internal solenoid circuit
c1282 - yaw rate sensor bias circuit malfunction
c1285 - lateral accelerometer circuit
c1296 - master cylinder pressure sensor circuit
all of these codes are current. will a scan tool get ride of these for good? thanks for any help!!
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thanks for the fast reply. i'm pretty sure it's the right part (#9376711). if the control unit connector is that big bunch of wires, i'm pretty sure it's plugged in good. i took it off and put it back on. thanks, dw
Drifting
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From: bloomfield nj
there are 2 under the hood and 1 in the r/f floor.the 1 in the floor is a 20a for the stop light switch[do you have brake lights???],the 2 under the hood are for the controller i think 1 is a 40[says abs],the other says abstrns,i think this one is a 10a.also make sure you hooked the ground wire back up to the unit[it bolts to the side]
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well... brake lights work, 2 fuses under the hood are ok. the ground wire is secure (i never took it off). weird... hard to believe i would of got a bad unit from chevy? do you think this is a scan tool thing? thanks!!
Drifting
Joined: Oct 2003
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From: bloomfield nj
you didn't take the unit off???? are you sure you got the ebcm on straight without bending the pins over???????? i would take the control unit back off and see if anything went bla.you have to get it on straight or you can create what you have.JMO
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i didn't take it off completely, i removed the mounting bolts and lifted it up a couple inches. the ebcm came off pretty easily. i'll do it again. yuk... i'll let you know what happens after i get more stitches in my arms. thanks again, dw
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just looked a my old ebcm. i don't think i could of bent any pins. the pins are recessed and well protected. i took a picture of my old one but can't figure out how to upload it. i'll reinstall the new one anyway. thanks, dw
Le Mans Master
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St. Jude Donor '04
Try to erase the codes, just because they are showing current doesn't mean they are actually hard faults right now.
If you erase them and they come back as current faults then you need to worry.
If you erase them and they come back as current faults then you need to worry.
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ok, time to worry. reinstalled, same thing. i erased the codes, they all came back. one thing which maybe i should of mentioned before... when i erase the codes, instead of the dic saying no more codes it says 3 codes. so...i'll have 6 or 7 codes, push reset to erase, then the dic will say 3 codes (which i cannot erase no matter how many times i hit reset). i'm still wondering if a scan tool will erase them for good? thanks for the help!
Le Mans Master
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St. Jude Donor '04
A scan tool won't have any more power to erase a fault code than the way your doing it.
First which 3 codes will not erase?
Did you only change the EBCM or did you also change the BPMV, the brake pressure modulator valve bolts to the side of the electronic brake control module.
C1247 - (circuit description): The brake fluid level switch monitors the level of the brake fluid in the master cylinder.
C1271&72 - The system relay is energized when the ignition is on. The system relay supplies voltage to the valve solenoids and the pump motor. This voltage is referred to as the system voltage. The EBCM microprocessor activates the valve solenoids by grounding the control circuit.
C1282 - The vehicle stability enhancement system (vses) is activated by the EBCM calculating the desired yaw rate and comparing it to the actual yaw rate input.
C1285 - This one is pretty much the same as C1282.
C1296 - The EBCM uses the input from the brake fluid pressure sensor for more accurate braking control during VSES.
First which 3 codes will not erase?
Did you only change the EBCM or did you also change the BPMV, the brake pressure modulator valve bolts to the side of the electronic brake control module.
C1247 - (circuit description): The brake fluid level switch monitors the level of the brake fluid in the master cylinder.
C1271&72 - The system relay is energized when the ignition is on. The system relay supplies voltage to the valve solenoids and the pump motor. This voltage is referred to as the system voltage. The EBCM microprocessor activates the valve solenoids by grounding the control circuit.
C1282 - The vehicle stability enhancement system (vses) is activated by the EBCM calculating the desired yaw rate and comparing it to the actual yaw rate input.
C1285 - This one is pretty much the same as C1282.
C1296 - The EBCM uses the input from the brake fluid pressure sensor for more accurate braking control during VSES.
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well here's what happens... i'll have 6 codes on the dic, i press reset, the dic says 3 codes (no matter how many times i press reset it still say's 3 codes). i run the diagnostic again & the same 6 codes are on the dic. i only changed the ebcm. take it out back & shoot it?
Le Mans Master
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St. Jude Donor '04
According to the service manual once the new EBCM is bolted to the BPMV and the wiring is plugged in and the unit is bolted down, it tells you to turn the key on but not start the car and then run the diagnostic from here, this completes the install as long as the diagnostic checks out.
Since yours is not checking out then my best guess would be you got a bad EBCM or once that is for a different year car.
Do you get the same faults with both EBCMs?
BTW, what city are you in?
Since yours is not checking out then my best guess would be you got a bad EBCM or once that is for a different year car.
Do you get the same faults with both EBCMs?
BTW, what city are you in?
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after i put the new one in it fixed my old codes. the codes i'm getting now are the new codes. i'm 99% sure i have the right part. i'm in gardena (southern california). i decided to take it to westcoast corvettes, they told me NEW ones need to be flashed. probably about 35 minutes away with no traffic (yeah right). now that you mention it... when i installed it the first time i can't remember if i ran the diagnostic first or started the car first. the second time i installed it i ran the diagnostic first. could that be it??? thanks!!