This test was done with the used AVP or SBA pump sitting on the cowl as there is no need for ground on the pump, it has a male female connection of 6 wires I believe at the top of the AVP. When connected to the tahoe the used pump purrs and seems to work just fine sucking from the inlet hole that attaches to the brake booster. I have purchased a used (AVP or SBA pump) which I have plugged into my 03 tahoe which does not have a problem with SBB light. The below explanation of what caused the light to come on helps but does not address what issues I have and will share. I have sourced every thread I could find. The 03 Yukon has "SERVICE BRAKE BOOSTER" (SBB) light on when i bot the truck 6 months ago. I have and 03 tahoe with 139K and 03 Yukon with 90k.
#4 circuit brake booxter full#
This post is from SHADAMS on the GM Inside News forum, so that full credit is given to this outstanding explanation this person should be commended. Vacuum pump(AVP) or (SBA) noted below attached to 03 Tahoe and 03 Yukon. I have no clue what the fix is since the mentioned post didn't include any solutions.īelow is an overview of the Aux. There seems to be a checklist the car is going through at startup and one of the items it checks is voltage in a wire from the 4-pin connector on the alternator to an electric vacum pump? Mine is 14.8 while I believe stock is 14.2-14.4.
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One post I saw somewhere said that a guy had a similar problem and he thought it was because some high output alternators have slightly higher volts. I've been googling this for quite some time but I have found very little info. I put the new one back in and the error message came back. The problem is related to the alternator swap since I put the old one back in this afternoon and the error message was gone. It failed the inspection because of the error message in the DIC though so I have to fix this now.
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I had the car through the bi-yearly inspection today and the brakes ARE in fact good. It comes on every time I drive and wont go away until I push one of the steering wheel buttons.īrakes seems to work great. After starting up, everything is fine but as soon as I start driving I get this Service Brake Booster message in the DIC panel. I think the stock alternator was 130A.Īfter putting in the new alternator, my charging problems went away and it seems to have worked great during the cold winter months here in Norway. It was not performing as well as before so I bought a new Powermaster 220A unit. Problem started when I replaced the stock alternator a while ago. I have been searching this excellent forum but couldn't find an answer. If you are unsure about performing this process on your own, get one of the mobile technicians from YourMechanic to come to your home or office and replace your vehicle’s vacuum booster sensor.I really could need some input on a problem on my 2003 Tahoe. If any warning lights remain illuminated, you may need to visit a local repair facility or auto part store to clear and reset the system. Sometimes, simply replacing a faulty component may not automatically reset any warning lights that are present. Depress the brake pedal a few times to verify whether you have vacuum assist. Start the vehicle and allow the vacuum pressure to build back up in the brake booster. Also, put back any other components and trim panels that may have been removed to access the vacuum sensor.
#4 circuit brake booxter install#
Once the old sensor is removed, you can install the new one.Įnsure that you replace and tighten the clamps that were removed earlier.
![4 circuit brake booxter 4 circuit brake booxter](https://www.picclickimg.com/00/s/MTAwMFgxMDAw/z/ZCgAAOSwKOJYJaeY/$/Medium-Dual-Circuit-Remote-Vacuum-Brake-Servo-_1.jpg)
Once you locate the sensor, remove any trim pieces and brackets that may be present so that you can access the pressure sensor.Īfter you gain access, use the appropriate pliers to remove the hose clamps and then pry the vacuum sensor from the vacuum hose. Verify the sensor location for your specific vehicle before you begin or attempt the replacement. However, the vacuum line may not be directly visible in front of the brake booster as it may run behind and/or under the windshield cowl. Usually, the vacuum pressure sensor is located in the vacuum line to the brake booster. Step 1: Determine the location of the vacuum brake pressure sensor. Part 1 of 2: Locate the vacuum pressure sensor Since the brake system on your car is vital for your safety, ensure that you get this issue fixed as soon as possible. If vacuum levels fall or if the vacuum pressure sensor fails, your car can have an illuminated Check Engine Light and/or a hard brake pedal. The sensor is typically located in the vacuum line from the vacuum pump to the brake booster. This sensor monitors vacuum levels to the brake booster to ensure proper power brake operation. The brake booster vacuum pressure sensor is found in most vehicles equipped with an electric or engine-driven vacuum pump.