U0161 Low Generic / SAE

U0161: Lost Communication With Compass Module

Network and Communication Lost Communication

What to do

This one is at the bottom of the priority list, and the car is entirely unaffected.

The compass has stopped reporting altogether. That is different from a compass reading wrongly — and the difference matters, because the usual fix for a wrong compass is to drive slow circles in an open space to recalibrate it, and that will not help here. There is nothing to calibrate; the connection has gone.

So do not spend time on the calibration procedure. Ask for the wiring to be checked instead.

One thing worth mentioning: has anything been done to the windscreen, the interior mirror, the headlining or the roof recently? The compass sensor usually lives in the mirror or the headlining above the screen, and its wiring runs up the pillar and across the roof — exactly where a windscreen replacement, a mirror change, a dashcam fitting or an aerial retrofit puts somebody's hands. A fault dating from any of those is almost certainly a connector.

Nothing about driving depends on this, though the satellite navigation may be slightly less accurate in tunnels and built-up areas where it relies on dead reckoning.

What this code means

The compass module has stopped being heard from. The general reasoning is at U0100, and U0462 explains why a compass reading wrongly is usually not broken at all.

That distinction is the whole of this page, and it is worth making because the two codes attract entirely different work.

A compass that reads wrongly wants calibration — driving slow circles in an open space — because the vehicle's own magnetism has changed. A compass module that has stopped being heard from wants a wire. No amount of circling helps, and the calibration procedure will not complete because there is nothing to complete it.

So if the heading is simply absent rather than wrong, skip the calibration and check the connection.

Where it lives is the useful part. The compass sensor is normally in the interior mirror, in the headlining above the windscreen, or in the roof console — so its wiring runs up the A-pillar and across the headlining, exactly where a windscreen replacement, a mirror change, a dashcam installation or an aerial retrofit puts hands. A fault dating from any of those is that harness or that connector.

Nothing about driving the vehicle depends on this. The consequence is confined to the display and, on some vehicles, to the navigation system's dead-reckoning when satellite reception is poor — see U0163.

Likely causes

Start here

Less common

Symptoms

Components involved

Information, not instruction

CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.

Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.

Community experience

Be the first to write this up

Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.

What makes one worth reading:

The car — make, model, year and engine. The same fault behaves differently on each.
What you measured, not only what you replaced.
What actually fixed it — or that nothing did, which is worth knowing too.