Acura said the security horn on some 1999 3.2 TL models may sound muffled or weak when activated by the remote unit's panic button.
The most likely cause for the muffled sound is the horn's bracket halves vibrating against each other. Modifying the bracket should take care of the problem.
Start the job by loosening the horn mounting bolt, then jostle the horn back and forth until you break the paint bond between it and the lower retaining bracket. Remove the horn from the vehicle.
Next, insert a screwdriver between the bracket halves on the horn at the bolt-hole end. Work the screwdriver as far down as you can go, then pry the bracket halves apart 1/2- to 3/4-inch and install an 8mm flat washer to maintain the gap. Make sure the washer is positioned over the mounting bolt hole.
To complete the repair, reattach the horn to the lower retaining bracket using a new bolt, then press the panic button on the remote to verify that the horn functions properly.
Some 2000-02 V8 Tundra pickups built before VIN 5TBBT44142S304208, as well as 2001-02 Sequoias built before VIN 5TDZT34A42S110570, may turn on the check engine light and log trouble code P0135 and/or P0155 in computer memory.
The genesis of the problem, Toyota said, lies in the inability of the existing upstream oxygen sensors to warm up within the prescribed time limits of the vehicles' computer software. Newly designed oxygen sensors are now available to eliminate the problem. Order part #89465-34150 for bank 1 of the engine and part #89465-34140 for the sensor on bank 2.
Owners of 2002-03 four-wheel-drive Chevy Trail Blazer, GMC Envoy and Olds Bravada sport-utility vehicles may complain of a high-pitched squeal, squeak or whistle emanating from the front axle area, particularly when the outside temperature is below 40 degrees F.
According to GM, the most probable cause of the noise is a dry seal at the outboard end of the right axle intermediate shaft housing and/or the left side of the differential carrier. Newly designed seals with better lubricity (part #12479302 for the intermediate shaft; part #12471618 for the differential carrier) are now available to alleviate the concern.
To help differentiate between a wheel bearing problem and the seal issue, have a helper get in the truck, then raise the vehicle on a lift. With the four-wheel-drive system engaged and the transmission in gear, spray one seal then the other with water or silicone spray. If the noise diminishes, replace the offending seal(s), as required.
“Factory Fixes” is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected]