CUCV Ground Locations: (all models except M1010)
Diagrams are located in the back of the TM 9-2320-289-34 Technical Manual
Diagram E-1 - Battery 1 - Smaller wire at negative terminal. Attaches to the radiator support in front of the front battery
Diagram E-1 - Ground Strap - Attaches between the cab and the right rear intake manifold bolt. Many times this wire is missing.
Diagram E-1 - Water-In-Fuel - wire is spliced into the engine harness and the end attaches to the right rear intake manifold bolt. Shows to also supply a ground to the GP controller.
Diagram E-1 - Starter Relay - wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-1 - Starter Solenoid - uses it housing as the ground.
Diagram E-3 - Main Battery Ground - 2 gauge black from Negative Term Board behind rear battery - attaches to the front right frame
Diagram E-3 - Combination Switch - This is the brake combination valve on the front cross member - uses it housing as the ground.
Diagram E-3 - Single Wire Switches and Sensors - Oil Pressure, Transmission Downshift, Fuel Shutoff, Fast Idle Solenoid, Cold Advance Control, Coolant Temp - uses their housing as the ground
Diagram E-4 - Park Brake Switch - Located at the top of the parking brake - uses its housing as the ground
Diagram E-4 - Fuel Gauge - Located on the circuit board of the instrument cluster - uses pin #9 of the circuit board - attaches to the harness ground wire
Diagram E-4 - Seat Belt Retractor - Located at the drivers outside seatbelt - uses its housing as the ground
Diagram E-4 - Bus Bar Ground - the 6 legged terminal block - Located near the parking brake. Harness wire is bolted to the cab. THIS IS THE MAIN UNDER DASH GROUND
Diagram E-4 - Tank Sending Unit - Located on the left frame rail
Diagram E-7 - Glow plug controller ground - 18 ga black wire attached to the main ground block behind rear battery
Diagram E-9 - Battery 1 - Smaller wire at negative terminal. Attaches to the radiator support in front of the front battery (repeat)
Diagram E-9 - Generator 1 Ground - Attaches to the GEN1 isolated ground terminal and the left front intake manifold bolt
Diagram E-9 - Generator 2 Suppressor - A capacitor bolted to the rear of the GEN2. Most have been removed as they are only needed with military radios
Diagram E-9 - Generator 2 Relay -Located next to the starter relay. Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-13 - Right Headlight Body - located at the right side radiator support
Diagram E-13 - Left Headlight Body - located at the left side radiator support
Diagram E-13 - Voltmeter & Heater Control Lights - Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake,
Diagram E-13 - Terminal #9 lead on cluster -Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-14 – Left Tail Light - bolted to the cab
Diagram E-14 - Right Tail Light - bolted to the cab
Diagram E-14 - Trailer Electrical Connection - bolted to frame
Diagram E-14 - Headlight Switch - uses it housing as the ground.
Diagram E-18 - Front Blackout Light Harness - attached to left radiator support
Diagram E-18 - Rear Blackout Light Harness - attached to frame
Diagram E-20 - Horn - uses it housing as the ground.
Diagram E-20 - Horn Suppressor - capacitor at horn - uses it housing as the ground. Good idea to remove it. If bad it can cause the headlight fuse to overheat.
Diagram E-20 - Blower - uses it housing as the ground. Sometimes an additional ground wire to the cab is needed
Diagram E-20 - Horn Button - uses it housing as the ground.
Diagram E-20 - Wiper Control - Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-20 - Wiper Motor Suppressors Located at the wiper motor - uses it housing as the ground. Good idea to remove as bad suppressors can cause slow wipers
One thing you will notice is that the dash wiring harness shares a common ground wire. If the connection of this wire is dirty then all sorts of electrical gremilins can/will happen.
The wire is connected to the the Buss Bar Ground next to the parking brake. It can be in many locations but will be in the general area. (depends on who was working that day)
Another MAJOR issue with grounds is the metal tab inside the tail/parking lights. It corrodes and ends up breaking off.
If anyone finds errors or additions, please let a moderator know.
Diagrams are located in the back of the TM 9-2320-289-34 Technical Manual
Diagram E-1 - Battery 1 - Smaller wire at negative terminal. Attaches to the radiator support in front of the front battery
Diagram E-1 - Ground Strap - Attaches between the cab and the right rear intake manifold bolt. Many times this wire is missing.
Diagram E-1 - Water-In-Fuel - wire is spliced into the engine harness and the end attaches to the right rear intake manifold bolt. Shows to also supply a ground to the GP controller.
Diagram E-1 - Starter Relay - wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-1 - Starter Solenoid - uses it housing as the ground.
Diagram E-3 - Main Battery Ground - 2 gauge black from Negative Term Board behind rear battery - attaches to the front right frame
Diagram E-3 - Combination Switch - This is the brake combination valve on the front cross member - uses it housing as the ground.
Diagram E-3 - Single Wire Switches and Sensors - Oil Pressure, Transmission Downshift, Fuel Shutoff, Fast Idle Solenoid, Cold Advance Control, Coolant Temp - uses their housing as the ground
Diagram E-4 - Park Brake Switch - Located at the top of the parking brake - uses its housing as the ground
Diagram E-4 - Fuel Gauge - Located on the circuit board of the instrument cluster - uses pin #9 of the circuit board - attaches to the harness ground wire
Diagram E-4 - Seat Belt Retractor - Located at the drivers outside seatbelt - uses its housing as the ground
Diagram E-4 - Bus Bar Ground - the 6 legged terminal block - Located near the parking brake. Harness wire is bolted to the cab. THIS IS THE MAIN UNDER DASH GROUND
Diagram E-4 - Tank Sending Unit - Located on the left frame rail
Diagram E-7 - Glow plug controller ground - 18 ga black wire attached to the main ground block behind rear battery
Diagram E-9 - Battery 1 - Smaller wire at negative terminal. Attaches to the radiator support in front of the front battery (repeat)
Diagram E-9 - Generator 1 Ground - Attaches to the GEN1 isolated ground terminal and the left front intake manifold bolt
Diagram E-9 - Generator 2 Suppressor - A capacitor bolted to the rear of the GEN2. Most have been removed as they are only needed with military radios
Diagram E-9 - Generator 2 Relay -Located next to the starter relay. Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-13 - Right Headlight Body - located at the right side radiator support
Diagram E-13 - Left Headlight Body - located at the left side radiator support
Diagram E-13 - Voltmeter & Heater Control Lights - Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake,
Diagram E-13 - Terminal #9 lead on cluster -Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-14 – Left Tail Light - bolted to the cab
Diagram E-14 - Right Tail Light - bolted to the cab
Diagram E-14 - Trailer Electrical Connection - bolted to frame
Diagram E-14 - Headlight Switch - uses it housing as the ground.
Diagram E-18 - Front Blackout Light Harness - attached to left radiator support
Diagram E-18 - Rear Blackout Light Harness - attached to frame
Diagram E-20 - Horn - uses it housing as the ground.
Diagram E-20 - Horn Suppressor - capacitor at horn - uses it housing as the ground. Good idea to remove it. If bad it can cause the headlight fuse to overheat.
Diagram E-20 - Blower - uses it housing as the ground. Sometimes an additional ground wire to the cab is needed
Diagram E-20 - Horn Button - uses it housing as the ground.
Diagram E-20 - Wiper Control - Wire is spliced into the under dash wiring harness and terminates at the 6-legged Bus Bar Ground near the parking brake
Diagram E-20 - Wiper Motor Suppressors Located at the wiper motor - uses it housing as the ground. Good idea to remove as bad suppressors can cause slow wipers
One thing you will notice is that the dash wiring harness shares a common ground wire. If the connection of this wire is dirty then all sorts of electrical gremilins can/will happen.
The wire is connected to the the Buss Bar Ground next to the parking brake. It can be in many locations but will be in the general area. (depends on who was working that day)
Another MAJOR issue with grounds is the metal tab inside the tail/parking lights. It corrodes and ends up breaking off.
If anyone finds errors or additions, please let a moderator know.
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