Operation CHARM: Car repair manuals for everyone.
Home >> Ford >> 2003 >> Thunderbird V8-3.9L VIN A >> Repair and Diagnosis >> Wiper and Washer Systems >> Testing and Inspection >> Pinpoint Tests >> Test Q
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Test Q

PINPOINT TEST Q: THE INTERMITTENT WIPER SPEED DOES NOT OPERATE CORRECTLY (HIGH/LOW SPEEDS OK)


Test Q1-Q2:






Test Q2-Q4:






Normal Operation
The windshield wiper motor receives inputs from the multifunction switch circuits 31S-XL50 (BK/OG), 31S-XL51 (BK/GN), 31S-XL52 (BK/RD), and 31S-XL53 (BK/WH). The wiper motor module (internal) controls the wiper run/park relay (internal) using internal circuitry to control the windshield wiper motor in conjunction with the wiper HI/LO relay (internal).

Possible Causes
- check circuit 31S-XL51 (BK/GN) for open
- multifunction switch
- windshield wiper motor
pro multis · About Operation CHARM