Body, generic

B0900 Wiper Motor Front Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

Open J2012 material, factory manuals and NHTSA bulletins contain no entry for B0900, so it is unconfirmed. The title concerns the windscreen wiper motor circuit. GM-era Saab models diagnose it at the relays: the 9-3 sets B3874 06 or B3875 06 when the low- or high-speed relay output stays below 6 V, so the wipers stop, run constantly or only at high speed. GM's 2011 Saab 9-5 logs B3715 and B3875 for the relay control lines and B371A when the park-switch signal does not match the switch position. FMVSS 104 asks for two or more speeds: a fast one with 45 or more wipes a minute and a slower one with 20 or more, separated by 15 or more. Bosch supplies brushless and reversing wiper drives; TI names position control with stall detection as a design requirement. Rear: B0910.

Likely causes

Wiper relay sticking or with burnt contacts
Wiper motor worn or park switch faulty
Seized linkage overloading the motor
Damaged wiring in the scuttle area

Symptoms

  • Wipers do not run, run continuously or only at one speed
  • Wipers stop outside the park position
  • Poor visibility in rain; do not drive in wet weather until repaired

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–500
Time0.3–2.5 h

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

Parts involved

front wiper motorwiper relaybody control module

Related codes

B0910B0920B0220B0190B0192

References: saabwisonline.com, saabwisonline.com, saabwisonline.com, saabwisonline.com.