Mechanics

ABS LIGHT COMES ON WHEN PARKING BRAKE APPLIED

1997 Infiniti I30 • 70,000 miles



couple of odd things going on with the brakes:
1) if you apply the parking brake the abs light comes on

2) have low pedal, but if you pump it up it gets firm. The master cylinder diagnosis was good, so its not that.

3) abs light has come on and then gone off when car restarted, couple of days later may come on again.

there are no leaks, system was properly bleed and pads are excellent.
please tell me how to fix this stuff before I dump a bunch of money in without it fixing anything.
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Bkpbest
January 29, 2012.



The abs should not come on with parking brake.
Low pedal could be air trapped in the system. Did you have it pressure bled?
You need a shop to pull the abs code and do a proper diag to find the failure.

Roy


ASEMaster6371
Jan 29, 2012.
Yes, it was pressure bled.
I figured the dealership would be best place to go for an odd thing. I tried with my scan tool but nothing came up. Do you need a seperate one for abs?
It boggled my mind and the mechanic at dealer when I told him light came on when parking brake applied.


Tiny
Bkpbest
Jan 29, 2012.
Yes, a real scanner is needed to access codes. You need a new shop with better experienced techs. The low pedal concerns me.

Roy


ASEMaster6371
Jan 29, 2012.
I will ask around to see where a good shop is around here. What is the concern? Is it because it has to be pumped once or twice to get firm? Is there anything I should look for concerning the low pedal?


Tiny
Bkpbest
Jan 29, 2012.
Low pedal is not normal and of course I am concerned you do not have full braking power. Get it checked asap it is dangerous to worry about pumping your brakes to get a good pedal.

Roy


ASEMaster6371
Jan 29, 2012.
For this year model, you can retrieve the codes manually.

SELF-DIAGNOSTICS

ABS Warning Light

When a problem occurs in ABS, the ABS warning light on left side of instrument cluster comes on. ABS warning light flashes Diagnostic Trouble Codes (DTCs) when Data Link Connector (DLC) terminal is grounded.

Self-Diagnostic Procedure

1. Drive vehicle at speed greater than 20 MPH for at least one minute. Turn ignition off. Locate DLC in fuse block on left side of instrument panel. See Fig. 6. Connect a jumper wire between ground and terminal "L" at DLC.

2. Turn ignition on. Ensure brake pedal is not depressed. After 3.6 seconds, ABS warning light begins to flash Diagnostic Trouble Codes (DTCs). If only DTC 12 (system functioning properly) is set, and ABS is not functioning properly, diagnose system by symptom.

NOTE: DTCs will stop flashing after 5 minutes. To reactivate code display, turn ignition off and back to on.

3. After completing repairs, erase DTCs. Repeat steps 1) and 2) to ensure codes have been cleared. Disconnect jumper wire from DLC connector. ABS warning light should go out after driving vehicle at speeds greater than 20 MPH for at least one minute. After
confirming proper warning light operation, test ABS in safe area.

Reading Diagnostic Trouble Codes

1. Follow steps in SELF-DIAGNOSTIC PROCEDURE under SELF-DIAGNOSTICS. Determine Diagnostic Trouble Code (DTC) by counting the number of times ABS warning light flashes. Up to 3 codes can be stored at a time, with the most recent code displayed first.

2. ABS light first flashes DTC 12, which is the start code. DTCs will then be flashed. See Fig. 7. After codes are flashed, start DTC 12 will again be displayed and DTCs repeated.

Clearing Diagnostic Trouble Codes

To clear codes, ground terminal "L" at Data Link Connector (DLC) 3 times within a 12.5-second period. See Fig. 6. ABS warning light should stay on during erase process and go out when operation is complete. Ensure codes have been erased. Start DTC 12 will flash even after DTCs are cleared.


KHLow2008
Jan 29, 2012.
Ok. So we have put a new master cylnder in and benched bleed it. Result is nothing different. All that is left is the calipers but the car doesn't pull to the side nor is there uneven wear on pads. Two mechanics are baffeled by this. There think about dismantle entire system to figure it out
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Tiny
Bkpbest
Feb 2, 2012.

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