Question about 1989 Honda Civic
It appears that the fuel pump relay is working properly. I am able to direct wire the yellow w/black stripe wire coming out of the firewall in engine compartment and it initializes the fuel pump and engine will star. I then disconnect the jumper wire and engine continues to run properly. Where in the heck is the main relay? I've searched behind the fuse box but cannot find it ( thinking it may be the problem ) ? Any help is welcomed....Jake
On your car the main relay should be behind the fuse box inside under the dash. You might have to unbolt the fusebox to find it but it is a black relay that is about 2-2 1/2" wide. It is very likely that is your problem. The fuse box only has two 10mm nuts holding it in, just be careful to not pull on any wires to hard when trying to remove it. That relay can be a little pricey but it one of the most common failure on the older Hondas like ours. I hope this helps.
Posted on Aug 15, 2008
Tips for a great answer:
Apr 04, 2016 | 2006 Toyota Corolla CE
Nov 28, 2015 | Cars & Trucks
Feb 26, 2014 | 2002 GMC Sierra 1500
Jun 24, 2012 | Cars & Trucks
· Fuel Pump secondary circuit shorted to power
· Fuel pump relay contacts always closed
· Open in fuel pump monitor (FPM) circuit between ECU and connection to POWER TO PUMP circuit
· Heated Exhaust Gas Oxygen (HEGO) sensor shorted to power
· faulty ECU
Engine Does Not Start:
· Open inertia switch or inertia switch circuit
· Open in or between ECU and fuel pump (This includes open in fuel pump brushes/windings)
· faulty ground connection at fuel pump
The easiest way to check this circuit is to go to the fuel pump relay. If the relay clicks when the key is turned to the "RUN" position, then the inertia switch circuit is ok.
The Pink/Black wire starts from the fuel pump relay and goes two directions. One side goes back to the fuel pump. The other side is the fuel pump monitor circuit and goes to pin #8 at the ECU. This wire should only be hot for a second or two when the ignition is turned to the RUN position.
The fuel pump relay receives power on the Black/yellow wire. It comes from a fusible link at the power distribution center. This wire should be hot at all times.
If all the above is working as designed, them you probably have a bad fuel pump.
Feb 13, 2011 | 1992 Ford Thunderbird
Feb 09, 2011 | Ford F-150 Cars & Trucks
Nov 03, 2010 | 2001 Ford F150 Styleside SuperCrew
Mar 09, 2010 | 1997 Honda Prelude
Mar 30, 2009 | 1993 Mercury Topaz
May 22, 2014 | 1989 Honda Civic
80 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: