Capt. John Deering":dlwjl9k2 said:
anybody know how to test a yam. engine temp (a) gauge and the (b) sensor on the motor, when i cut the key to on the meter moves off zero a bit, underway the needle does not rise as eng. temp. increases?
Capt John:
To test (b), turn ignition key ON, but don't start it. Now, on any OMC and almost every other motor, there is a tan wire on the top of each head that originates out of a port near each thermostat. It's been a while since I've worked on my bros Yams, so I can't tell if that's where it is or what the color is. Yam uses funky colored wiring, see at the end of this post.
Regardless, the drill is take-apart the 2-piece plug and ground the powerpack side to the block .. the overheat alarm should sound.
(a) See if this may help on your other problems, this is Teleflex "troublshooting guide to gauges and senders", click
here.
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Yamaha "non-standard color" coded wiring:
BLACK = Ground
RED = Battery Positive; SW3 Oil warning red light V4
YELLOW = Ignition ON 12-volts; Four-stroke lighting coil
BLUE = Instrument lights, choke, choke circuit,
Ground potential oil transfer, High speed Charge Coil
GREEN = Tachometer signal, lighting coil lead, knock sensor
ORANGE = Trim position sensor
PINK = Oil and overheat signal ground
WHITE = Ignition stop circuit, SW1 oil transfer off position V4
BROWN = Start circuitl Low speed charge coil; Positive "+" potential
to oil transfer pump; SW2 transfer on position V4
GRAY = Warning circuit lead; Over-rev. control; Four-stroke tachometer
SKY BLUE = Trim up
LIGHT GREEN = Trim down
YELLOW/Red = Diagnostic lead from ECU
PURPLE = ECU ground to enrichment solenoid V76
BLACK/Yellow = Thermo sensor
BLACK/Red = Remote oil tank ground return, PBS to tachometer,
Low speed charge coil
BLACK/White = Ignition coil primary lead
GREEN/Blue = Crank position sensor
GREEN/Red = Red oil warning light ground through SW3 in main tank oil
sensor to tachometer
GREEN/White = Crank position sender; Lighting coil lead to rectifier
BLUE/Green = Main tank oil level sensor SW2 oil transfer circuit
BLUE/Red = Main tank oil level sensor SW3. No oil warning circuit
BLUE/White = Main tank oil level sensor SW1; Oil transfer OFF circuit
BLUE/Yellow = Shift cut switch
PURPLE/Red = OX66 #1 injector
PURPLE/Black = OX66 #2 injector
PURPLE/Yellow = OX66 #3 injector
PURPLE/Green = OX66 #4 injector
PURPLE/Blue = OX66 #5 injector
PURPLE/White = OX66 #6 injector
RED/Yellow = Key on power through fuel relay pump; power to ECU;
Fuel pump and fuel injectors
WHITE/Red = #1 pulser V6
WHITE/Black = #2 pulser V6
WHITE/Yellow = #3 pulser V6
WHITE/Green = #4 pulser V6
WHITE/Blue = #5 pulser V6
WHITE/Brown = #6 pulser V6
YELLOW/White = Electric fuel pump for electri carb system (ECS)
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