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Fuel Pump Circuit Opening Relay Testing

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Old 04-23-2008, 07:08 PM   #1
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Fuel Pump Circuit Opening Relay Testing

Vehicle = 1986 4Runner Auto Transmission.

Thanks to the '85 4Runner FSM and more thanks to 4Crawler ,I have been able to determine that I might have a weak Fuel Pump Circuit Opening Relay like he had... There is no power at the fuel pump when I crank it, but there is 12 V when I jumper the Fuel Pump Check Connector (...or maybe I have a bad fuel pump switch in the Air Flow Meter?)

How do you test the Circuit Opening Relay? There are 5 contacts! not labeled at all on the relay body.
Circuit Opening Relay Contacts
Circuit Opening Relay Back

How to you test the Fuel Pump Switch in the Air Flow Meter?

and what is ECU STA?

Thanks in advance,


I should have spent more time with the FSM and less time in the YotaTech galleries...

Last edited by Toyotero; 04-23-2008 at 07:45 PM.
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Old 04-23-2008, 11:09 PM   #2
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Well, it looks like you answered one of your questions. I was going to say look in the FSM or 4crawler's site for testing the air flow meter. One of the circuits tested in the procedure is for the FP switch. I forget offhand which one. If it passes, no need to test the COR as you've just narrowed the problem down to it....considering the FP is working when you jump the connector.

Context is everything....
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freckles, shmeckles... that was your acne reflecting on my pearlescent skin.
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Old 04-23-2008, 11:09 PM
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05, 1986, 2004, 22re, 4runner, circuit, fuel, mgt, open, opening, pump, relay, schematic, supra, testing, toyota

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