Why does the brake dash warning light come on when engine is idling and go out when engine speeds up.
This seems to happen only when engine is cold. Stop at stop light -light comes on, leave
stop light - light goes out?
It could be something as simple as vacuum loss to the brake booster. When you are driving you are creating more vacuum. When you are at idle, you create less. If there is a small leak in a vacuum line, it will be noticeable when at idle and negligible when driving at speed.
Also check the fluid level in the master cylinder. It could be low. HTH. -Jim
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