newbie with need of a help

[adamus]

Hello All,


I'm Adam and I just became lucky owner of 1998 CRM 250 AR,

I tried to search the forum for some info however i found nothing on my problem.
Basically as soon as the bike starts the Temp Light comes on, i purchased genuine honda temp sensor
however that didn't solve the problem i also tested the wire which goes to the sensor and it is ok.

Could anyone have any suggestions maybe?

Thank you for help

Adam

[Gammakeith]

Welcome! Unfortunately, that is quite a complex bit of wiring to trouble shoot. Are you handy with the multimeter? The output from the temp sender goes to the main ECU which then sends a signal to the "control box" when it thinks the temperature is too high. The control box then converts the signal to something LED friendly and feeds it directly. I would check for any wiring faults first. I suspect the ECU triggers the control box by earthing the feed to it. Thus, worth checking that wire first to see if its earthing anywhere. In the FAQ, there is a summary of the AR wiring which will help if you want to check ECU inputs/outputs.

Good luck!

Keith

[adamus]

hi Keith,


Thank you for your reply, I have tested the sensor wire and it's not earthing and its free from damage


Adam

[Gammakeith]

Hi Adam,

If the sensor and feed from sensor to ECU is fine (have you checked continuity at the actual ECU plug?) then it must be one of the following;

1. Faulty ECU
2. Faulty wire from ECU to control box
3. Faulty Control box or associated wiring
4. Faulty wire from control box to speedo housing

In my experience, most electrical issues in older motorbikes are from owner botches and damaged or corroded wiring. Thus, I would start with (2) and (4) above.

Keith