Ok, So It Is Brand New To Me. Super Clean, Very Minor Rot Rear Bottom Of Cab. Its A Real Nice Black 250 4 Door (actually A 3 Door / 1 1/2 Doors Each Side) Super Cab. Only Have A Few Minor Problems. Maybe You Can Help Or Point Me To It.

1) The Blower Only Has High Speed. I Changed The Resistor Bank And Dash Switch. Still Only High Speed. Is There A Relay Associated With The Low Speeds? Is There A Fusible Link? Can't Find A Wiring Diagram For It.

2) When I Put Gas In It, The Guage Can Take As Much As 5 Minutes To Register. Bad (saturated) Sending Unit? Lazy Guage?

PINPOINT TEST I: THE BLOWER MOTOR OPERATES CONTINUOUSLY IN HIGH SPEED
CONDITIONS DETAILS/RESULTS/ACTIONS
I1 CHECK THE FUNCTION SELECTOR SWITCH



Set the blower motor speed to maximum.

Check for blower motor operation in each function selector switch position.


Does the blower motor operate in all of the function selector positions except OFF?
Yes
GO to I2.

No
GO to I3.
I2 CHECK CIRCUIT 261 (OG/BK) FOR A SHORT TO GROUND




disconnect Blower Motor C168



disconnect Blower Motor Resistor C169



disconnect Blower Motor Switch C168


Measure the resistance between the blower motor connector C168, circuit 261 (OG/BK) and ground.


Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new blower motor switch. REFER to Section 412-04. TEST the system for normal operation.

No
REPAIR circuit 261 (OG/BK) for a short to ground. TEST the system for normal operation.
I3 CHECK CIRCUIT 399 (BN/YE) FOR A SHORT TO GROUND




disconnect Function Selector Switch C296



disconnect Blower Motor Relay


Measure the resistance between the function selector switch connector C296 pin 3, circuit 399 (BN/YE) and ground.


Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new function selector switch. REFER to Section 412-04. TEST the system for normal operation.

No
REPAIR circuit 399 (BN/YE) for a short to ground. TEST the system for normal operation.

Thank You For Your Suggestions. I Will Try And Get It Into The Shop In The Next Few Days And Check It Out. I Will Let You Know What I Find.