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V850R

1997 Volvo 850r Wagon ECU Constant Power

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Hello I have been fighting an issue and I believe it is because my ECU is not getting constant power. I think that the constant power is suppose to go to the 101/102 Relay. I tested all the fuses and fuse 1 ECU power gets power when I turn the ignition on as it should but when I tried to test the 101/102 relay base to see if that was getting constant power I could not get the test light to light up.

1. Is 101/102 the constant power supply I am looking for?

2. How do I properly test the relay base to see if it has constant power?

3. If I am way off. Where do if find the constant power and how do I test to make sure it is getting constant power?

Thanks!

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Uh, I think it's #3?

The ecu gets constant (non-switched) 12v pwr on pin A26 directly from the battery; it does not go through any relays.

There are some relays that are fed constant pwr, but doubt 101/102 is one of them.

What's the issue you're trying to fix?

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Hey gdog thanks for getting back to me!

I live in California :( and I am trying to pass smog. My cars emission monitors set without problem But the problem is that when I turn the car off the monitors go back to not ready. I believe it is because my ECU is losing power when the car is off so it is not able to save that the monitors are set. So my idea is to check constant power.

1. California allows two monitors to be not ready for my year.

2. I have asked over ten smog shops if they would run the test without turning off the car they all say that they have to turn it off to check that the CEL is working properly.

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I don’t know how to do it, but if you wanted to ride dirty.  Rig up another battery somewhere 

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On 11/18/2020 at 12:47 AM, V850R said:

Hey gdog thanks for getting back to me!

I live in California :( and I am trying to pass smog. My cars emission monitors set without problem But the problem is that when I turn the car off the monitors go back to not ready. I believe it is because my ECU is losing power when the car is off so it is not able to save that the monitors are set. So my idea is to check constant power.

1. California allows two monitors to be not ready for my year.

2. I have asked over ten smog shops if they would run the test without turning off the car they all say that they have to turn it off to check that the CEL is working properly.

CA is such a PITA when it comes to smog tests!  Not sure off-hand about the 2 monitor limit but volvo 96 to 98 MYs have known issues regarding OBD2 monitors which should get you a waiver on that front.

Read more:

 

http://volvospeed.com/vs_forum/topic/170393-convert-daily-driver-850-to-44/?do=findComment&comment=2381729

 

Edited by gdog

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