motorrad2 Posted November 27, 2015 Share Posted November 27, 2015 Stopped at a convenience store the other day, came back out and no start. Cranks over fine, just has no spark. Checked (all w/ key in the "ON" position): No spark from coil while cranking. No power to coil. Voltage to accessories, fuel pump, etc. Fusible links good, voltage is present. Fuses (5 and 11 too!), all ok, voltage is present. Distributor: Rotor spins, is tight to distributor shaft. Ignition relay: Removed and tested, switches circuits correctly. Ignition relay connector: Voltage across each of the two "switched" circuits Ignition relay connector: NO VOLTAGE TO THE RELAY! My bet is that power is not getting through the ignition switch to the ignition relay. Link to comment Share on other sites More sharing options...
naru Posted November 27, 2015 Share Posted November 27, 2015 SPFI? "Ignition" relay has nothing to do w/coil power. If you have power on BOTH sides of fuse 11,but none at coil +,then you have a wiring problem between the fuse and coil. Ditto for fuse 12 if you have no power on the ignition relay coil. If the fuses have power,ignition switch is OK. Sounds like a loose harness connector. Link to comment Share on other sites More sharing options...
motorrad2 Posted November 27, 2015 Author Share Posted November 27, 2015 What is the purpose of the ignition relay, and why do you put the word "ignition" in quotes? Do you believe it misnamed? When should there be power to the relay's "switching" pin circuits, which then closes the circuits for the two "switched" circuits? Those two circuits then go off into the ECU? Shouldn't there be voltage to the ignition relay when the ignition switch is in the "ON" position? I've removed the ignition switch, and found continuity between the B/W wire and: ACC position: Black/Blue ON position: Black/Blue and Black START position: Black/Red, Black, and Black/Yellow I don't believe the switch is bad either. Link to comment Share on other sites More sharing options...
motorrad2 Posted November 27, 2015 Author Share Posted November 27, 2015 Just pulled the coil, which is a new (< 2 year old) Mallory 29219. Metal-crimp connector on coil to distributor high-tension wire looks fried, as if burnt, is brittle, and broken. Primary resistance is 2.1 ohms, secondary 10.1K ohms. Primary resistance is higher than stock by about an ohm. Link to comment Share on other sites More sharing options...
naru Posted November 28, 2015 Share Posted November 28, 2015 Yes,I consider the ignition relay misnamed.It does not power the coil. Your lack of power at the coil is not due to an ignition relay circuit fault,but,most likely shares a common cause. The ignition relay powers the ECU. There should be voltage on the relay coil w/the key on. Ignition coil sounds like a problem,but,that does not explain the lack of power. Link to comment Share on other sites More sharing options...
motorrad2 Posted November 28, 2015 Author Share Posted November 28, 2015 Naru, I saw you in another posting for a no-spark condition on a Loyale, and that thread has been most helpful. I finally found a diagram for the system, which has been helpful as well in understanding the path undertaken by current as it flows from the battery to the coil. Battery --> Fusible link (1.25) --> ignition switch --> Fuse 11 --> B/W wire to 3-pin connector --> B/W wire to 7-pin connector -->B/W wire to the coil So, next step for me is to test continuity along that path. Questions: "The ignition relay powers the ECU.": Which ECU pin is for power-in? Is that 27? "There should be voltage on the relay coil w/the key on.": What's the relay coil? Do you mean ignition relay (it is labeled as such, "ignition relay", on the diagram)? I'm not certain of the current path to the ignition relay yet. The coil situation I have, I measured >3 ohms resistance on the primary circuit, what are the consequences of using a higher-than-specified resistance coil? I'm picking up a new one today from NAPA, but even that one specified no resistance value, although it is listed for use on the car. The heat buildup at the high-tension connection is concerning. Link to comment Share on other sites More sharing options...
naru Posted November 28, 2015 Share Posted November 28, 2015 Ignition relay powers pins 21,29 and 49. ECU receives unswitched power on 27. See page 46 section 2-7 of the ea82 manual here http://jdfinley.com/file-downloads/subaru-manuals/ Relay coil=Ignition relay control coil(inside the relay) Excessive ignition coil resistance results in weak or no spark. Link to comment Share on other sites More sharing options...
motorrad2 Posted November 29, 2015 Author Share Posted November 29, 2015 OK, have power to coil. Did nothing I'm aware of to get it there except replace the coil. Still no spark. I do have power to pin 27 (ign switch OFF). There is no continuity between 27 and 29 (with ign switch ON). These two should be switched at the ign. relay. I have no power to the ignition relay, to either the G/W or B terminals. The R/Bl, R, and B/W have voltage, the W does not. Wires in connector to ign. relay: R: always on from fusible link R/Bl: to pin 49 on ECU B/W: Power from fuse 5 W: to pin 41 and 29 on ECU I need power to that ignition relay! Link to comment Share on other sites More sharing options...
maozebong Posted November 29, 2015 Share Posted November 29, 2015 you should follow the trouble tree in the FSM pdf, it sounds like youre chasing your tail. the trouble tree has you check ecu power and grounds first, and then the crank angle sensor. if your ecu doesnt have power and grounds then it can't power the fuel pump or ignition relays. coil is continuously powered, and gets the ground switched via the igniter riveted to the coil bracket. igniter bracket needs clean ground. the ignition relay is powered by the ECM (g/w, pin 28, specific connector not listed. the B wire at the ign relay is a ground, it shouldnt have voltage, or more than .5ohms to ground) check that you have power and ground at the ECM, and that it outputs 12v to the crank angle sensor in the distributor. no distributor signal, no spark or fuel pump. pcm failures are not unheard of, and my first subaru needed one to get it running. Link to comment Share on other sites More sharing options...
naru Posted November 29, 2015 Share Posted November 29, 2015 you should follow the trouble tree in the FSM pdf, it sounds like youre chasing your tail. the trouble tree has you check ecu power and grounds first, and then the crank angle sensor. if your ecu doesnt have power and grounds then it can't power the fuel pump or ignition relays. coil is continuously powered, and gets the ground switched via the igniter riveted to the coil bracket. igniter bracket needs clean ground. the ignition relay is powered by the ECM (g/w, pin 28, specific connector not listed. the B wire at the ign relay is a ground, it shouldnt have voltage, or more than .5ohms to ground) check that you have power and ground at the ECM, and that it outputs 12v to the crank angle sensor in the distributor. no distributor signal, no spark or fuel pump. pcm failures are not unheard of, and my first subaru needed one to get it running. You are wrong on several points. The ignition coil is not continuously powered.Power is switched by the ignition switch. The ignition relay is not powered by the ECM.It is the other way around. Power from fuse 12 flows to pin 38 and also thru the diode to the ignition relay coil and pin 28. 1 Link to comment Share on other sites More sharing options...
naru Posted November 29, 2015 Share Posted November 29, 2015 OK, have power to coil. Did nothing I'm aware of to get it there except replace the coil. Still no spark. I do have power to pin 27 (ign switch OFF). There is no continuity between 27 and 29 (with ign switch ON). These two should be switched at the ign. relay. I have no power to the ignition relay, to either the G/W or B terminals. The R/Bl, R, and B/W have voltage, the W does not. Wires in connector to ign. relay: R: always on from fusible link R/Bl: to pin 49 on ECU B/W: Power from fuse 5 W: to pin 41 and 29 on ECU I need power to that ignition relay! Got power on both sides of fuse 12? If so,I suspect the diode is open or poorly connected. Presuming the fuse is OK,you could run a new wire w/an inline diode between fuse 12 and ignition relay G/W to bypass the existing faulty circuit. Link to comment Share on other sites More sharing options...
motorrad2 Posted November 30, 2015 Author Share Posted November 30, 2015 Thanks maozebong, on page 46 of section 2-7 I began following the tree at step "1": Resistance of terminals 30,42,44, and 51 are between 1.3 and 1.6 ohms. The resistances are all OK, according to the FSM. Voltage at terminal 29, 41, and 49 is zero. Voltage at 27 is 12.57V. FSM says there should be 10V minimum at all four!!! Question on terminal 49: This RL wire runs from ECU pin 49 to the ignition relay RL wire. There is no voltage at the ECU terminal (with the connector disconnected from the ECU), but there is voltage at the ignition relay RL wire with the connector connected to the ECU. So, power must run FROM ECU pin 49 THROUGH terminal 49 TO the ignition relay. Why then does the FSM have us test terminal 49? Note that with the ECU terminals all plugged into the ECU, there is 12V+ voltage at the ignition terminal R, RL, and B/W. At W, voltage is -.33 V. If voltage is <10V, next step in the FSM tree directs to check "battery terminals, fuse, ignition relay and ignition switch". If OK, next step is to "repair harness" Battery terminals: Good. Fuses: 5,11,12,20 fuses are good (continuity), voltage present at all. Ignition relay: Tested by applying 12V to G/W, B to ground. Continuity then measured across B-B/W and R-RL. Ignition switch: Voltage gets to fuse 11 in the "ON" position. Measured continuity between the B/W wire and, in the ACC position: Black/Blue, in the ON position: Black/Blue and Black, and in the START position: Black/Red, Black, and Black/Yellow. Link to comment Share on other sites More sharing options...
motorrad2 Posted November 30, 2015 Author Share Posted November 30, 2015 (edited) Naru, power on just one side of fuse 12. Yes, I've considered exactly what you proposed to get power to G/W at the relay. I've had it for today, I'll try that tomorrow morning. Edited November 30, 2015 by motorrad2 Link to comment Share on other sites More sharing options...
naru Posted November 30, 2015 Share Posted November 30, 2015 Naru, power on just one side of fuse 12. Yes, I've considered exactly what you proposed to get power to G/W at the relay. I've had it for today, I'll try that tomorrow morning. If the fuse only has power on one side.it is BLOWN! Link to comment Share on other sites More sharing options...
motorrad2 Posted November 30, 2015 Author Share Posted November 30, 2015 Naru, I wish it were so simple. Fuse out, power on one side. Fuse in, power on both. Fuses are fine! Link to comment Share on other sites More sharing options...
motorrad2 Posted November 30, 2015 Author Share Posted November 30, 2015 (edited) The diode shown as connector F109. If it was faulty and stopped flow in both directions, that would explain no voltage to the ignition relay/ECU power terminals. Diode test result: infinity in one direction, .544 ohms in the opposite. Looking for specs on that diode. Question: where does the power come from to feed the ignition relay? I see ECU terminal 28, GW, is a "Self-shutoff signal". I have no voltage at terminal 28, yet it appears to be the "power-in" to the ignition relay. No voltage at the ignition relay means no power to 29, 41, and 49: power terminals for the ECU. Edited November 30, 2015 by motorrad2 Link to comment Share on other sites More sharing options...
motorrad2 Posted December 1, 2015 Author Share Posted December 1, 2015 Problem solved. At connector F109, where the diode plugs in, there are actually TWO G/W wired into that connector. Mine had one G/W and one RL. The second G/W wire had broken off down inside the connector, and the wire was just a little stub coming out of the back of the electrical-taped bundle. Splice repair and it started right up. Thank you all for your help!! Link to comment Share on other sites More sharing options...
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