P0856 Traction Control
07-03-2014 | 08:13 PM
#12
Senior Member
Joined: 12-24-2007
Posts: 2,873
From: Seville. OH
Yes - the car has ABS.
Quick update - I got an Advance Auto scancode this afternoon. The only return was "ABS disabled."
I'm hoping to get the car into a shop tomorrow to check the hubs and ECM. In the meantime, I'd like to do a diy visual check of the ECM wiring and grounds. I don't know which underhood component it is or how to access it. Can anyone point me in the right direction?
Thanks again.
Quick update - I got an Advance Auto scancode this afternoon. The only return was "ABS disabled."
I'm hoping to get the car into a shop tomorrow to check the hubs and ECM. In the meantime, I'd like to do a diy visual check of the ECM wiring and grounds. I don't know which underhood component it is or how to access it. Can anyone point me in the right direction?
Thanks again.
If there is not a code in the abs side then the input to the traction control in being lost between the abs side and the traction control side.
The traction control is built into the abs module and it is located under the hood forward of the fuse box (PDC)
07-10-2014 | 10:55 AM
#13
Thread Starter
Member
Joined: 06-04-2011
Posts: 59
From: Denver, Colorado
Here's the follow up:
I got the car into a Chevy dealership yesterday. Picked it up this morning.
"Check engine light and traction control light and hard shifting."
"DTC codes P0013 and P0014. Replaced intake and exhaust camshaft actuator solenoids - cleaned throttle body. Engine air filter replaced."
The repair bill totaled $533.03, including $100 diagnostics.
The dealer told me the ABS related code was essentially a ghost triggered by incorrect sensor inputs associated with the actual faults.
Thanks for all the the input as the issue was worked through.
I got the car into a Chevy dealership yesterday. Picked it up this morning.
"Check engine light and traction control light and hard shifting."
"DTC codes P0013 and P0014. Replaced intake and exhaust camshaft actuator solenoids - cleaned throttle body. Engine air filter replaced."
The repair bill totaled $533.03, including $100 diagnostics.
The dealer told me the ABS related code was essentially a ghost triggered by incorrect sensor inputs associated with the actual faults.
Thanks for all the the input as the issue was worked through.
07-11-2014 | 06:49 PM
#15
Thread Starter
Member
Joined: 06-04-2011
Posts: 59
From: Denver, Colorado
I gave them the whole chronology starting with the initial P0856, and the subsequent "ABS disabled". They told me they found nothing going on with the ABS system. I know they road tested the car, not just around the block but about 5 miles or so, after the actuator replacements to check again for brake related problems or codes and there were none. So far, everything is back to normal. Traction control light and check engine light are dark and the car runs fine. Time will tell.
As for the bill, the dealer charged less for the diagnostics than the indy shops around here. The work is warranteed. If this problem is solved and crossed off the list, I'm happy. I can't afford to take more time on this one trying to find a less expensive option. I'm back to work and back to frying bigger fishes :)
As for the bill, the dealer charged less for the diagnostics than the indy shops around here. The work is warranteed. If this problem is solved and crossed off the list, I'm happy. I can't afford to take more time on this one trying to find a less expensive option. I'm back to work and back to frying bigger fishes :)
05-22-2022 | 07:04 PM
#18
Senior Member
Joined: 04-06-2020
Posts: 920
From: Missouri
The traction control works by reading the speed of each front wheel and cutting back the power if one wheel turns too much faster than the other. It reads the speed by a pulse as the reluctor teeth pass in close proximity to the sensor. If the hub bearing gets a little loose, the space between the reluctor and sensor gets too big to read the speed correctly causing the intermittent problem. Sometimes rust or mud on the reluctor can interfere with the sensor but at nearly 100k miles, it is likely that the hubs could need to be replaced if they haven't been already.
05-23-2022 | 06:41 AM
#20
Administrator
Joined: 10-13-2011
Posts: 37,831
From: Welland,Ont Canada
JM4 is the RPO for antilock front disc / rear drum brakes
JL4 is the RPO code for active brake control
different diameter tires or one low pressure tire with cause the wheel speeds sensors to think there’s a problem and light up the ABS and TC light!
JL4 is the RPO code for active brake control
different diameter tires or one low pressure tire with cause the wheel speeds sensors to think there’s a problem and light up the ABS and TC light!
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