Diagnostic Aids

Ask customer about driving habits and/or unusual traffic conditions such as heavy stop and go driving. Check brake switch for proper adjustment. Inspect wiring for poor connections at PCM and at brake switch connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.