Just got in my truck to head home from work and both the ABS light
and the Parking Brake light were lit solid. No fluid leaking and
pedal action was fine. Tested it a little in front of the office
and drove home with one foot on the parking brake.
If the speed sensor (typically - from what I've read) near or on
the rear axle fails, will this light the Parking Brake lamp as
If not, where should I start checking?
That's what I was wondering. Does OBDII store code for anything
that will light an ABS or brake light? And are there various
levels of OBDII readers? Meaning, can the auto parts stores see a
code for this?
ABS *seems* to work. I did the best I could trying to lock them
up on a dirt road, but the bed was full. I'm fairly certain I
could at least feel one or two chatters...
-Cruise control isn't working - CC itself or the dash indicator
-Blower fan isn't working at all - don't even hear the relay click
between position 4 and 5.
-Heater controls are stuck on high - moving them through the range
produces no change in temp.
-Heat/Cool position switch isn't working. No matter where it's
set, air blows through the dash vents.
-I can't find any blown fuses.
Am I thinking along the right lines when I'm thinking there has to
be a bad ground somewhere?
I'm not sure, but I think that if there is a problem with the ABS, it will
illuminate both the ABS and Brake lamps. After all, the Brake warning lamp
is a general brake system malfunction indicator, not just a parking brake
warning indicator. You might check the ABS fuse under the hood or have a
dealer check the system with a scan tool. If it is a problem with the ABS
then the brakes will continue to function like non-ABS brakes - that is, you
won't see a difference under normal conditions, but if you slam the brakes
on, one or more wheels may lock up and skid.
Yeah, I was looking for a gravel road to test that theory out on
heading home from work tonight.
Will the ABS fuse failing cause it to light the dash lights? Will
the typical code reader at AutoZone (or whoever) be able to read a
stored code on this or do they mainly just do emissions stuff?
I would start with the easy stuff first. Make sure the Brake fluid is not
low. Some masters have a float in them and even with full fluid, the float
is stuck down and will cause the brake light to be on. Make sure the Brake
and ABS fuses are good. Check and make sure ALL rear Brake lights are
working including center, this on some cars will trip the ABS light. If all
that is good, then scan for ABS codes. A cheap OBDII scanner will NOT read
ABS codes even though it plugs into the same port. You need a scanner that
can read ABS codes. Once it tells you what the problem is, if it tells you,
you need to know what to do with that info because a cheap scanner is not
going to tell you anything on how to go about checking the problem out and
Yes, when the ABS light is ON, your brake system is now acting like a
NON-ABS system and will lock up, with the Brake light on also, I would get
it checked out pretty quick. Brakes are series business and not something
to take lightly. I've seen brake work many times that was a complete
screw-up from the owner trying to work on it and just ends up costing more
money in the end to be fixed right.
This is the cheapest ABS scan tool I've seen. I have no Idea how well it
works. If you want to spend that kind of money or just take it to a shop
that can scan for ABS codes that way.
(Amazon.com product link shortened)06760344&sr=8-1
Had a similar failure on a 2000 Silverado. Turned out to be the fluid level
sensor on the brake fluid reservoir on top of the power brake booster.
The part was like $70 bucks for the reservoir with sensor.
ABS systems do NOT throw out OBDII codes, it throws out ABS codes and you
need a scanner that scans for ABS codes, a cheap OBDII scanner won't see a
thing. As for a stuck float, like I said in my last message, it easy enough
to check, Do you have a electrical plug going to the bottom of the fluid
reservoir? If so then there's a float in the master. If the fluid is so
dirty that you can't see the float, there are ways to still check. You
could also usually just unplug the connector and see if the light goes off.
On my 03 Silverado there looks to be a place for the Sensor to be installed
at on the bottom of the reservoir, but it doesn't have a fluid level sensor
there. My fluid though is looking kind of dark. It's 5 years old and
Original brakes that are still in great shape. I think I'm going to have to
flush all that dirty fluid out pretty quick. Should do a Radiator flush
also, it's time. Time flies, it's general maintenance time.
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