OP
@swiss1939 avatar
UTC

Ossessionato
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
Joined: UTC
Posts: 4110
Location: Staten Island, NY
 
Ossessionato
@swiss1939 avatar
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
Joined: UTC
Posts: 4110
Location: Staten Island, NY
UTC quote
Ive wired up a Koso temperature gauge and it works fine when the ignition is on, no engine running, but once the engine starts it has problems: gauge cycles through the "power on" loop endlessly. I've checked all connections, nothing is loose. The gauge needs between 6v and 12v to work, and while engine running power never dips below 12v. I've had it wired to the orange wire from ignition, the purple wire from ignition and the gray battery positive wire to horn (cross checked with the wiring diagram. All present the same issue.

battery on, no engine:
battery on, engine on:
Just wondering if there is some wiring issue that I need to solve, or if this could just be a defective gauge?

here is the wiring for power to the gauge (connected to the orange ignition wire and black ground wire)
Forum member supplied image with no explanatory text
@waspmike avatar
UTC

Ossessionato
LXV 150 3v ie. Midnight Blue (Sold) Now Honda Zoomer X
Joined: UTC
Posts: 4130
Location: Kingdom of Lanna
 
Ossessionato
@waspmike avatar
LXV 150 3v ie. Midnight Blue (Sold) Now Honda Zoomer X
Joined: UTC
Posts: 4130
Location: Kingdom of Lanna
UTC quote
Basic stuff?

- What happens if the spark plug sensor is disconnected?
- What happens if you hold the gauge in your hand?
Ie. not physically mounted on the bike
@socalguy avatar
UTC

bodgemaster
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7223
Location: So Cal
 
bodgemaster
@socalguy avatar
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7223
Location: So Cal
UTC quote
Try using a resistor spark plug or resistor cap.
OP
@swiss1939 avatar
UTC

Ossessionato
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
Joined: UTC
Posts: 4110
Location: Staten Island, NY
 
Ossessionato
@swiss1939 avatar
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
Joined: UTC
Posts: 4110
Location: Staten Island, NY
UTC quote
Resistor spark plug solved the issue. Thanks! knew it had to be something with irregular power signal, but had no idea how to solve it.
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