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Old 16th May 2022, 20:41   #11
Kampo
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Originally Posted by T-Cut View Post
Does the radiator fan start when you start the engine?
Does the temperature gauge stay in its ignition-off position?

TC
hi T cut i know this is now quite an old post but i suffer from both of these symptoms. i had posted here a while back about the fact the car had been static for some time. at the time i was told to check the cables in the v leading to the coolant sensor in case any rodents had eaten them. i m yet to achieve this i m hoping i ll be able to in next few weeks as i m battling taking off the inlet manifold with work duties etc however i want to ask can it be coincidental that i also have no revs at the same time? i m hoping the coolant temp staying at cold and the fan kicking in immediately after i start the engine is isolated to the engine revs not showing- i m really hoping it s not ecu as i never found the plenum to have got any water and i do clean the plug hole fairly regularly. do you have any idea other than replacing coolant temp sensor what else i could be faced with and how else to tackle the rev meter issue? i have done instrument cluster check and it all checks out good
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Old 17th May 2022, 07:16   #12
SD1too
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... i m hoping the coolant temp staying at cold and the fan kicking in immediately after i start the engine is isolated to the engine revs not showing ...
Hi Marios,

Normally the gauge reading full cold with the radiator fan running means a problem with the coolant temperature sensor signal reaching the ECU. You're saying that also your rev. counter isn't working even though the engine runs normally?

Both the coolant temperature and rev. counter signals are transmitted from the ECM to the instrument pack on the CAN bus. Do you have any other apparently unrelated faults which might confirm this?

Simon
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Last edited by SD1too; 17th May 2022 at 08:24.. Reason: Updating
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Old 17th May 2022, 08:49   #13
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Originally Posted by Kampo View Post
i know this is an old post but this one plug next to the throttle body you have in the pic is not for the coolant temp sensor. did you ever find out?
I know that I'm five years too late with this response but it is the connector for the traction control throttle position sensor.

Simon
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Old 17th May 2022, 17:47   #14
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Hi Marios,

Normally the gauge reading full cold with the radiator fan running means a problem with the coolant temperature sensor signal reaching the ECU. You're saying that also your rev. counter isn't working even though the engine runs normally?

Both the coolant temperature and rev. counter signals are transmitted from the ECM to the instrument pack on the CAN bus. Do you have any other apparently unrelated faults which might confirm this?

Simon
Hi Simon they are the only two issues i have at the moment. Lights are working ok ac comes on ok i cannot see any other issue to indicate any other problem. Fuel gauge shows ok i m not sure about kms showing as i havent taken out in the road yet. Could it just be that i need to lookat coolant temp sensor as well as crankshaft pos sensor? Is the crankshaft pos sensor the one that engages revs or am i completely wrong? What gives the reading in the rev counter pulse to start with?
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Old 17th May 2022, 17:56   #15
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Is the crankshaft pos sensor the one that engages revs ...? What gives the reading in the rev counter pulse to start with?
The rev. counter is driven by the ECM (Engine Control Module) via the CAN bus. The crankshaft position sensor signal enables the ECM to determine the engine speed and therefore drive the rev. counter.

Does that help?

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