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Home >> Oldsmobile >> 1986 >> Toronado >> Repair and Diagnosis >> Engine Performance >> System >> BCM System, Part II >> ECM Trouble Code Charts - Trouble Shooting >> Code B660, Cruise Control Not In Drive (Riviera) >> Notes
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Code B660, Cruise Control Not In Drive (Riviera): Notes

Fig 1: Code B660 Flowchart, Cruise Control Not in Drive (Riviera)
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Fig 2: Code B660, Cruise Control Not in Drive (Riviera)
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Fig 3: Code B660 Schematic, Cruise Control Not in Drive (Riviera)
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The BCM which issues the control signals to the servo, checks to make sure the vehicle is in a forward gear before allowing cruise control operation. This is done by the BCM receiving the ECM's inputs for Park and Neutral over the data line and by circuit 24 feeding directly to the BCM for Reverse gear status (high on circuit 24 indicates Reverse).

Code B660 will set if the cruise control is engaged and the BCM receives a signal indication that the vehicle is in Park, Reverse, or Neutral. During the time the failure is present, the BCM will disengage the cruise control system.

  1. BCM input BI24 displays Reverse gear status, as "HIGH" or "LOW" depending on the voltage state at the BCM. The display should read "HIGH" only when the transaxle is in Reverse gear. If it reads "HIGH" in any other gear selection, the switch must be misadjusted, or circuit 24 (including the switch) is shorted to voltage.
  2. ECM input EI74 displays gear selector position status, as "HIGH" or "LOW", depending on the voltage state at the ECM. The display should read "LOW" only when the transaxle is in Park or Neutral. If it reads "LOW" in any other gear selection, the switch must be misadjusted, or circuit 434 (including the switch) is shorted to ground.
  3. Checks to see if the short to ground reading is due to the switch or the circuit.