1998 v70xc p0116 code

dr1vereye · Post by **dr1vereye** » 04 Oct 2015, 11:46

Hello, I need some advice please.
Dash light came from a very short drive. Code was p0166. Seems to be commonly a ect or thermostat.
While checking the wiring for cracks I thought I would test the fan. So I started the engine and turned on the a/c. No fan. Drove the car to reach the normal 3:00 temp guage range and checked. Still no fan.
I unplugged the ect, the engine would not start but the fan came on. Removed the key and the fan stayed on. Cleared the new code p0117. Started the engine and the fan turned off.
It would seem to me that the ect needs changing, and I will do the thermostat anyways.
What concerns me is does a faulty ect stop the fan from running while a/c is on? Or is that another issue.

dr1vereye · Post by **dr1vereye** » 04 Oct 2015, 17:17

The more I research, the more unsure I am.
I found one article that states that the a/c pressure activates the low engine fan speed. As my a/c is clutching on and off every 5 seconds, It could be low on refrigerant. (This was to be my next project...please don't be the evaporator....please don't be the evaporator).
I found another post suggesting replacing the fan relay switch to allow a/c to turn on engine fan.
And another post suggesting the ect can screw up the a/c turning on the fan.
As for the engine temperature switch. It sounds like the engine needs to be very very hot to turn on. Since it is Canada in the fall, It might simply not be getting hot enough. But SHOULD work with a/c on.

I guess I should verify the Low speed is working by jumping the switch (or beating on it)

Can anyone verify if refrigerant level can affect engine fan switch?

dr1vereye · Post by **dr1vereye** » 04 Oct 2015, 18:08

okay, turned on a/c, banged the relay and the fan worked and stayed on.
Grounded each connector in the middle relay plug, both the fast and slow speeds worked.
Reattached relay turned on a/c and fan did not work. When I banged it, the fan only spun a quarter turn, every bang.

Post by **kahl** » 04 Oct 2015, 18:53

I applaud your trouble shooting!! To me it appeares your relay is bad. if you shoot me a picture of the relay and or part number I will send you one. I have several boxes of relays.

dr1vereye · Post by **dr1vereye** » 06 Oct 2015, 19:25

thank you Kahl, I appreciate your offer to help me with this part.
My impatience ordered a part here in town. Unfortunately that was not the problem.
I hope my keeping this rather unfollowed post alive will:
a/ help me solve this problem that I still need to solve.
b/ help the next guy, as this forum saved my butt many time already.

Okay, Fan relay switch was not the solution. Both the old and new switch would move the fan a bit when whacked, but I confused wacking with time. Both relays would kick the engine cooling fan on in a/c mode if I just waited a minute regardless of wacking it or not. I am really wondering if the a/c needs to build pressure before it kicks the fan on. I have an appointment to get the a/c inspected tomorrow. (did I mention I hoped its not the evaporator?)
I will relay any new info as it comes.
Please help if you've gone through this already

Post by **Ozark Lee** » 06 Oct 2015, 20:45

The relay is told to turn on the fan on high speed by the ECU based on a high side A/C pressure signal. The A/C switch doesn't directly control the fan. If the R-134A charge is low and the A/C isn't actually working then the fan won't kick on.

...Lee

dr1vereye · Post by **dr1vereye** » 16 Oct 2015, 13:37

Returned the fan relay. A/c was charged and dye added. Seems good (so far). Fan turns on in a/c just not "immediately". As far as the error code. It has not shown up again. Maybe a hiccup? If it comes again I'll replace cts and thermostat.