Error code · Communication between control units

U1501 — LIN bus: communication fault with a device (GM code)

Safe to drive

For makes: Chevrolet, Cadillac, GMC

A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.

Possible causes

What you can do yourself

  1. First check the battery and terminals: at low voltage the LIN bus works erratically and the unit stores extra codes.
  2. Think about what stopped working (a window motor, the display, buttons, a sensor): that tells you which device isn’t answering. Check its connector and fuse.
  3. If the device was recently replaced, compare the part numbers: per a GM bulletin a similar-looking part from another year may not work on the bus.
  4. If the code is only in history and the car runs normally, clear it and see whether it comes back. If it doesn’t, no repair is needed.
OOleg’s tip: check the connector

Often the cause is simple — there is no contact in the connector (plug). Look at the connector from the back: remove the rubber seal and you will see whether a wire is corroded or has come off completely. Corrosion shows up as green deposits. Ideally, gently pull each wire towards you one at a time: a sound wire stays in place, while a corroded one simply comes off — it needs to be repaired.

Unplug and inspect connectors with the ignition off.

A number from the list of LIN bus codes (GM bulletin PIT5698): a unit isn’t getting an answer from a “smart” device — a motor, switch or sensor. This is the GM meaning (Chevrolet, Cadillac, GMC). On other makes this number means something else: if your car isn’t made by GM, change the make at the top.

Source: GM PIT5698A–F, 15-NA-087, PIT5231 (static.nhtsa.gov)

On Oleg’s website:Car wiring repair ↗

The explanation comes from the error code reference in the AvtoElektrik PRO app.

Need a mechanic’s help?

Couldn’t fix it yourself? Oleg, an auto electrician, does computer diagnostics and repairs: he comes out anywhere in Almaty or sees you at his workshop.

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Nearby codes

All codes in U02xx–U30xx →

Who keeps this reference

The reference is kept by Oleg Dmitriev, an auto electrician from Almaty with 26 years of experience: computer diagnostics of cars and trucks, repair of control units (ECUs). Can’t find the cause? Message him.