Powertrain, generic · Transmission

P0828 Up and Down Shift Switch Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

Many selectors read tap-up and tap-down over one shared wire with voltage steps or a resistor network; P0826–P0828 cover this shared circuit, P0815/P0816 the single directions. P0828 means the shared circuit voltage is too high – a short to positive, or on ground-switching switches with a pull-up also an open. No manufacturer document available to us uses it: Saab's 9-3 Sentronic reports this state as P0826 (above 6.7 V for more than 30 s), Saab's 9-4X as P0815 or P0816, and GM as P0826. Manual shifting would be disabled while automatic operation stays normal.

Likely causes

Signal wire shorted to positive
Signal wire or selector ground open (pulled-up input)
Selector assembly faulty
Control module

Symptoms

  • Tap or manual shifting not working
  • Transmission warning in the cluster
  • No effect on driving in automatic mode

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–600
Time0.5–2.5 h

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

Parts involved

tap shift switchgear selectorswitch wiringtransmission control module

Related codes

P0826P0827P085FP0815P0816

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