99 v70T5 new PNP, intermittent no crank...edit

jjnuttall · Post by **jjnuttall** » 19 Feb 2015, 08:16

Hey Gang !

Ive been reading many old threads on this problem because my 99 V70 is having the dreaded intermittent no-crank issue. I know some of you rigged a bypass from the starter test port and the solenoid and I'm wondering if you eventually arrived at a permanent solution ?

I have pulled the starter relay and jumper-ed the sockets to test and know the downstream starter circuit and starter works fine. I replaced that relay anyway (cheap insurance) it clicks in KPIII.

I replaced the PNP switch (easy DIY and $165 part) because the "rowing" and "start in neutral" techniques seemed to work, but the problem resurfaced. I'm done with replacing parts until I get a proper diagnosis.

Ive been examining the wiring diagrams... alot

I'm leaning towards the ground that the alarm module creates/supplies at terminal 86 for the starter relay to function (the dreaded kill switch?). I think the ground is missing intermittently (which could point to another failing relay), but I don't really know how to diagnose that. Am I looking for zero ohms at 86 to ground in KPII or KPIII ?

I read someone ground-ed out that circuit at the alarm module end under the dash to bypass alarm control. Could I also permanently ground that circuit socket 86 at the starter relay to something in that fuse box ? Whats the best way to do this.

I'd actually like to scrap (disable/bypass) the alarm system, and remove it from the equation. I don't need it. Same thing with the immobilizer !!! If I still have the problem after that then I'll look at the ignition switch.

so just today at noon.... cycled the key in door lock/unlock several times, no crank... key in ignition, several jiggle jiggle jiggle cycles, turn wheel several turns, several cycles on new PNP, thump left side ignition switch area, several KP 0 I II III cycles, no crank ..... pop the hood, finger on starter relay while son works key.... KPII feel click (alarm ground complete?) ... KPIII feel second click (30 to 87) and start.... go figure

baffeling

thanks for reading, hope you can help

John
Raleigh
99 V70T5 125,000 miles, good shape

draser · Post by **draser** » 19 Feb 2015, 10:39

Based on your description, you could simulate the alarm provided ground with a jumper wire and see if that works. If that ground is a relay contact, then I'd suspect relay, socket or wiring. If that ground is a "solid state" it's more complicated to test, you can still jump it though.