Gentlemen, I'm looking for a little guidance on my 4runner. I'm showing an error code 42 vehicle speed sensor circuit? I recently repaired the throttle position sensor on the vehicle, but this speed sensor code comes up when i connect the OBD reader? Does the speed sensor normally go out on these vehicles? Is it an easy fix? Are there any tricks for repairing this type of job? Any help would be greatly appreciated. Thank you...

 

The answer(s) depends on the year, transmission, and 2wd/4wd. Most likely, you have the electronic VSS1 which drives the speedometer, odometer, and speed signal to ECM. So, to get us started, is your speedometer working? If it is working, you likely have the "older" cable driven speedometer, where VSS1 is a reed switch inside the combination meter.

The transfer-case-mounted VSS1, can and does fail, but usually not until your rig hits 10-15 years old. Oh, right. RockAuto has the (aftermarket) part, but you may have to remove yours first to match the photographs. There are different units, and I can't tell you when and why, but they are different enough to distinguish using the photos. Removal is easy; there's a 3-pin connector, the unit is held in with a single bolt, and you rotate it (there's an o-ring that provides friction) back and forth to wiggle it out. Don't lose the nylon gear; the replacement unit won't have the gear.

 

Scope103, thank you for the help. I have a 1993 4runner 3.0 2wd automatic.

 

When code 42 is triggered does the computer do anything to the standard timing or fuel programs?

Does it pull back the timing and have the air/fuel run in a rich/safety mode?