Annoying Ticking Noise?

[mcfeeley]

Over the last year I have had an annoying :mad: ticking noise coming from the brake pedal/accelerator area. It has been intermittent but now comes on more frequently. It ticks about every second and doesn't speed up or slow down. Doesn't seem to be impacted by speed changes or any other controls. It is loud enough to hear even with the radio on. Often I can stop, turn the engine off, restart and it will be gone. Only to come back after driving for awhile. In the past, when I took it to be serviced it wasn't doing it so the mechanic couldn't diagnose. The vehicle is a 2003 LB7. It stopped for months but started back again.

Anyone have any ideas?:confused:

[DmaxMaverick]

If it doesn't change with engine/road speed, I'd suspect an HVAC actuator stepper motor. Possibly the recirc door.

[mcfeeley]

Thanks

Is this something they could check without hearing the noise?

[DmaxMaverick]

Probably, if the technician is competent. If you have auto climate control, the Tech II should be able to command any of the steppers independently. I don't know about the manual system. Otherwise, it's a matter of cycling the system through every possible setting. Worn/failing steppers can be an intermittent problem. And, as we know, intermittents are the most difficult of all problems to diagnose. Sure as the sun rises, they don't act up for the technician. Often, an HVAC error will set a code in the BCM, which requires a Tech II to read, and it won't trigger the SES lamp.