Odd ABS Light, service brake system message

[Ninja_Lawn_Guy]

Ok boss....I'll figure out what I'm gonna do and get back with ya well before then,,OK? thanks again

[Ninja_Lawn_Guy]

Thanx to those who offered help....got it scanned near home.

the codes are:

c0267 pump motor short or open circuit
c0268 same as above
c0291 ecbm failed signal bcm

so...is this common or something I can check?
let me know....I'd really appreciate it.

[mudseeker]

couldn't find anything for the 3rd code

CIRCUIT DESCRIPTION
The pump motor circuit is integral to the Brake Pressure Modulator Valve (BPMV) . The Electronic Brake Control Module (EBCM) microprocessor energizes the relay within the EBCM in order to supply the battery voltage to the high side of the pump motor. The EBCM microprocessor grounds the low side of the pump motor when activation of the pump motor is required.

CONDITIONS FOR SETTING DTC C0267

• The EBCM internal relay is on
• The pump motor is off
• Low voltage is present from the low side of the pump motor when high voltage is expected

CONDITIONS FOR SETTING DTC C0268

• Vehicle speed is 13 km/h (8 mph)
• The EBCM internal relay is on
• The pump motor is commanded ON and then OFF
• High voltage exists from the low side of the pump motor for 100 me when the voltage is expected to be low

ACTION TAKEN WHEN THE DTC SETS

• The ABS indicator lamp turns on
• The ABS disables

DTCs C0267/C0268 are ignition latched DTCs, which indicates that the above actions remain true until the ignition switch is turned to OFF (even if the cause of the DTC is intermittent).

CONDITIONS FOR CLEARING THE DTC

• Repair the conditions responsible for setting the DTC
• Use the Scan Tool Clear DTCs function

DIAGNOSTIC AIDS
The pump motor is integral with the BPMV. Do not service the pump motor separately. A poor power/ground connection at the 2-way EBCM connector or the 2-way motor harness from the EBCM to the pump motor can cause a DTC C0267. A seized pump motor, shorted pump motor windings or a poor power/ground at the 2-way EBCM connector can cause a DTC C0268. Replace the EBCM or the BPMV if the following tests show that the pump motor EBCM internal circuits have failed.


Important:</B> Reset the J 39200 test leads to zero prior to making any resistance measurements. Refer to the J 39200 in the user's manual.
TEST DESCRIPTION
The numbers below refer to the steps in the diagnostic table:

1. This step checks for an open pump motor circuit. The pump motor circuit resistance should not be above the 0.3 ohms. Reset the J 39200 test leads to zero prior to making this low resistance measurement.

1. This step determines the resistance of the EBCM ground circuit.

1. This step determines the ignition voltage available to the EBCM.

[Ninja_Lawn_Guy]

I get the process but it's not really something I think I can do...
just under experienced....The 3rd was a bad signal between EBCM and BCM<-(Body control module?)

[mudseeker]

check your 60 amp maxi fuse to start with, could be a simple fix like that.

[Ninja_Lawn_Guy]

I started with checking the plugs and wires leading to the pump and found a half-out plug soaked and filthy with splash dirt. Anyway, pulled it out and the truck played jinglebells one last time, both lights...I blew it out, cleaned the connectors....pushed it back in til it snapped....lights went off, haven't come back yet. "HOPEFULLY" that was the issue.

Thanks for your help mudseeker, I'll be back with future updates on this BS , I mean, situation.

[Ninja_Lawn_Guy]

didn't stop coming on...they must not have cleared them, or it's not fixed

probably not fixed

[mudseeker]

it may take a couple of drive cycles for the code to clear itself. or you could unhook the battery for awhile and let the computer relearn.

[Ninja_Lawn_Guy]

I went ahead and checked ALL the electrical connections and drained the old fluid, disconnected the battery for a half hour and it went off...stayed off for 2 drive cycles then came back on....now its on and off...crazy...the maxi fuse was fine, the MC sensor was loose but it clicked in place again. Just a strange set of circumstances I guess.
Or the pump is just on it's way out and sending the codes randomly.

[Ninja_Lawn_Guy]

WELL FRIENDS IT'S BACK AGAIN......Has been off for 2 weeks and today it's back....W T F?