Questions and Answers

Nissan Pathfinder Intermittent No Start Q. Vince, hoping you can help me with this small problem. 1993 Nissan Pathfinder 3.0 liter V-6 Manual transmission

Will not start occasionally. Will start some times. When started runs great!!! Starter is not turning when ignition in the start position. Hear clicking sound from relays in engine compartment. Not starter. With several attempts the starter will engage and engine will start.

Here is what I have done to try to solve the problem: suspected bad starter at first. Bought new starter. Worked for two months with no problems. Now same problem is back. Will start, won't start. Suspected weak battery, 5 years old. Purchased new 700 cranking amp battery. No affect. Same problem.

Suspected corroded terminal wires and ground wires. Replaced negative battery ground wire. Cleaned terminal wires and all wires connected to body and engine. Same problem.

Checked clutch interlock switch, small switch against fire wall of interior of car under the clutch pedal. Clutch has to be depressed in order to start car. Switch tested fine.

Temperature outside does not seemed to be an issue. Started on the coldest day of the year. Wouldn't start on a mild day. Doesn't seem to matter.

My only suspicions left are the ignition switch or the ignition relays. What's your opinion on the fact that it will start sometimes and not others and based on all the remedies I have tried?

A. This is one of the easiest starting systems to check. Start by checking for power at the black/yellow wire at the starter. If you have power there with the key in the START position, you have a bad starter.

If you don't, then go to the Clutch Interlock Relay. It's a big blue twin connector relay on the fender well near the battery. First check for power at both black/yellow wires. If you have no power there with the key in the start position, check for power at the black/yellow wire at the ignition switch. If you have power at the ignition switch and not at the relay, you have an open black/yellow wire. No power means a bad ignition switch.

If you have power at the Clutch Interlock Relay black/yellow wires with the key in the ON position check for power at the light green wire. No power there means bad relay. If you have power there, ground the light green wire. The relay should click and have power at the black/purple wire.

If not, bad relay. At the clutch interlock switch check for power. No power means an open light green wire. Stepping on the clutch should activate the relay. If not the switch is bad.

Based on my experience with this truck, and all Nissan trucks, the Clutch Interlock Relay is bad. I have a couple of test relays in my tool box to use as a quick test. I'll bet you 20 cents that it is that relay you hear clicking.

Added 2/5/04:

Thanks Vince for replying. A happy ending to this story. I did change the Interlock relay and sure enough the car starts every time. Thanks to your advice I was able to narrow my suspicions and fix the problem.

DG