My fan doesn't turn on and my ECU is not throwing any codes, I have a DX cluster in my car with a Si chassis harness, I am sure that doesn't help but would it cause it not to turn on the fan? The reason why I am worried is becuase my VTEC is not kicking in so I think it might be the coolant sensor not telling the ECU how hot the engine is to kick on the VTEC. Another thing is my speedometer is not working, I took out the cluster and made sure everything was right like the cable being in the back of the cluster all the way and it is, If this causes the VSS not to tell the ECU how fast my car is going then why would Vtec work if my timing was off? I am asking this becuase I recently replaced my timing belt, and had my timing off (stupid me) well VTEC was working with the timing off. I fixed the timing belt today and now my Vtec is not working. Any ideas?

 

well if the speedo isnt working the vtec will not work. check your speed sensor. top of tranny. somebodys got pics

 

new fan relay, fix speedometer.

 

I had the same problem with my cooling fan and VTEC. For me it was the Ground cable from the battery to the chassis and the motor were not making good contact. So I went and bought a new one and it fixed my problem.

 

wire the fan to ignition to make sure it s turning on . However my vtec does work w/o a speedo cable , I dont know why maybee because of the vafc. TRy replacing the coolant temp. sensor though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by riceboyEFsi &raquo;</TD></TR><TR><TD CLASS="quote">However my vtec does work w/o a speedo cable , I dont know why maybee because of the vafc. </TD></TR></TABLE>

Same with me. I don't think the PR3 checks speedo input to make sure the VTEC engages When I first got my engine installed I didn't connect the speedo cable; VTEC worked fine.

 

pull the two connectors from your CTS on the back of your block (2 prong sensor). place a jumper (wire, paper clip, etc) between the two connectors with the ignition switch turned to ON. if the fan kicks on, then the relay is most likely ok and your CTS is most likely the problem.

the reason is that the CTS provides ground to the fan relay and if the CTS is busted then it will never provide the ground for the relay and the fan will never turn on.

 

thats a good idea sleeper, I will try that right now and see if that works, same with the relay, I know the fan turns on.