Cruise Control Most Asked Question (ASN 1096-07)
Publication date: 1996-10-01Reference number: ASN 1096-07
CRUISE CONTROL MOST ASKED QUESTION
TECHNICAL SERVICE BULLETIN
CRUISE CONTROL Q & A
Model(s): All Acura Models Equipped W/Cruise Control
Category: Acura Service News
Group: Electrical
Bulletin No.: ASN 1096-07
Date: October, 1996
SERVICE INFORMATION
Here are a few cruise control questions and answers to help you understand its operation.
QUESTION 1
Is it normal for vehicle speed to vary slightly while the cruise control is on?
ANSWER
To maintain target speed, the ECU continually sends signals to the cruise control actuator to open and close the throttle. While this process happens very quickly, it's not instantaneous. A 2 to 3 mph variation is normal until the vehicle's speed "catches up" with the signal from the ECU.
QUESTION 2
Why does the vehicle lose speed when climbing a hill?
ANSWER
Most systems have an actuator that opens the throttle using manifold vacuum. Manifold vacuum decreases while the vehicle is climbing a hill. This means there's less vacuum available to operate the actuator.
QUESTION 3
Why doesn't the A/T downshift to maintain the target speed on a hill?
ANSWER
The cruise control system operates the throttle opening within a narrow range that's not enough to cause the A/T to downshift. (You can maintain target speed by depressing the accelerator pedal, or shifting to D3.)