Network, generic (extended)

U3032 Ignition Output Accessory/Off

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U3032 is the output counterpart of U3022: a line that a module drives to express the grouped state Accessory or Off, i.e. every power mode where the engine should stay off. Such grouping exists in real wiring. GM's 2012 pickup electrical manual shows a coded ignition circuit whose level is identical for a pulled key and for accessory, and changes once the key is inserted, the engine runs or cranks. A module generating a comparable output monitors the level at its pin and logs U3032 when the level differs from what it means to send, for instance accessory/off appearing while the vehicle runs. Receivers may then switch functions off on the move or stay awake when parked. No manufacturer documents U3032 publicly; codes such as U3022 or U302C stored in the receiving units show which side is wrong.

Likely causes

Output stage in the driving module stuck or failed
Output wire shorted to ground or voltage, or broken
Corroded or loose pin shifting the coded level
Retrofitted accessory tapped into the line

Symptoms

  • Accessories such as radio or sockets not matching the key or button position
  • Modules staying awake after shut-off, battery drained overnight
  • Related ignition input codes stored in other modules

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€30–600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

ignition outputoutput wiring

Related codes

U3022U302FU3031U302CU302B

References: law.cornell.edu, gmupfitter.com.