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1985 720 4x4 blue relay ticking question

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Our boy has a 85 4x4 5 speed truck that has a clicking inside under the passenger side dash that I don't know what it is. Any clue? Also under the hood behind the battery is a blue relay that's ticking but it look original and can't read anything on it. What is that relay? Truck runs and drives great but the ticking is annoying. I've tried goggle but had no luck. Oh, on his truck I can crank it without pushing in the clutch. Is that normal on older trucks?

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Pass side? Sounds like the choke heater relay. Usually this is a bad or badly charging alternator. Has it been replaced lately or the original one? Does the red charge light glow dimly or flicker? If you check battery voltage when running it should be close to 14v.

 

Do you have an O2 sensor in the exhaust?The relay is likely for the ECC carb. I don't know about this one... possibly the same as the choke heater relay.

 

 

The clutch interlock switch may have failed and a previous owner wired around the switch.

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I thought you just didn't have to push in the clutch to start these older rigs? Both of mine are that way, but that doesn't mean much. :-)

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Welcome to the odyssey! My 84 has a similar issue- a buzzing choke heater relay. I have been trying all sorts of things to track it down, with little luck so far. I will be watching your thread with great interest for possible solutions. Thanks for posting!

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I tried to do some digging on when the clutch safety switch was mandated, and I could not seem to find a solid answer. I even tried to go through the Federal Register and nothing was popping up except for an amendment in 2005, but I can not trace back to the original document it was amending. My theory is that there is no such law mandating them, but every automaker installs them to prevent such a ruling. My 86 doesn't have one, but I would like to place small wager that when Nissan went to the D21 in 1986.5, they installed a clutch safety switch. I wasn't alive then so I couldn't tell ya  :rofl:

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There is a clutch switch for emissions purposes, so if you have a switch it's likely this.

 

The clutch interlock is there for the same reason there is a key reminder buzzer.... for people who can't be trained to remember to place out of gear or clutch down to start.

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So sorry guys. This is my first post and I've been trying to figure out how to reply and such lol. Datzenmike your first comment makes since. The battery light on the dash is faded, then bright, then blicking so just acting crazy. So, the braided ground wire from firewall to motor is new now. Also the ground cables from the battery are new. Light is still on though. The blue relay is not clicking and no clicking inside cab either BUT the blower stopped working and no fuses are blown so may be that blue relay behind the battery is the heater relay. I got a picture but I can't figure out how to post it. Thanks so much for the quick response.

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I thought you just didn't have to push in the clutch to start these older rigs? Both of mine are that way, but that doesn't mean much. :-)

I kinda like it not having to push it in. I had a 81 that dad bought new and I got it in 87 but it's automatic . Then I got a new 89 hardbody and I had to push in clutch to start.

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There is a choke heater relay, has nothing to do with the heater in the cab. That's the one up under the dash passenger side.

 

 

There is also a heater relay for the heater fan. I wasn't sure where it was located. It may be the blue one.

 

 

The blue one should come on with the key. Without starting the engine turn the ignition on and listen for a click. If no click, swap the fuse for it, with a known good one... never trust a fuse on looks. If still not working the constant buzzing may have damaged it. Try unplugging it a couple of times. Last replace it.

 

 

If your red charge light is dimly on, or on and off, the chattering relays may come back. Unplug the fusible links attached to the positive battery terminals and reconnect so they are making good mechanical contact. Last check the voltage across the battery. A good charged battery will be 12.6-ish. Start and check. It should be14.5 -ish to start and quickly dropping to low 14s. Put headlamps and heater on high and there should be little change. If you have the original alternator likely the brushes have worn down. Yes you can throw on what is known as a 're-built' for very cheap but I would rather have an original from a wrecking yard as they have quality parts. New from Nissan they are over $300 so that shows how cheaply made and reliable the rebuilds are. I would try to replace the brushes 

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You will need to use a picture hosting site, other than Photobucket. You picture is loaded and kept there and you access the image code bring it here and add to your post.

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Ok cool. I will take the alternator off and take it to a shop that will rebuild it. Just had our oldest boy's starter rebuilt. I will check the blower also inside. Thank u so much for all the help. I will let ya know the outcome.

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The heater relay is mounted on the fuse box. From left to right there is a power window, heater and headlight relay.

 

Under hood by the battery, front to back.... ECC (carb) relay, ASCD (cruise control) inhibit and ACSD relay for auto trans.

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Thank you. I just pulled them and will take them to the parts store tomorrow and order them. Our boy said he is done and wants something else because it's not fast enough. His lost is my gain lol. I'm taking it over and I'm stoked!!! Granted I have alot of time invested in it and once I replaced these relays and alternator it will be perfect mechanically. This coming up summer I plan on painting it red. He is so gonna regret this decision lol

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Thank you. I just pulled them and will take them to the parts store tomorrow and order them. Our boy said he is done and wants something else because it's not fast enough. His lost is my gain lol. I'm taking it over and I'm stoked!!! Granted I have alot of time invested in it and once I replaced these relays and alternator it will be perfect mechanically. This coming up summer I plan on painting it red. He is so gonna regret this decision lol

Yeah he will. I wanted something fast, but I "got stuck" with a really heavily thrashed 720 I bought. I am glad I stuck with it though, fast isn't everything.

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You will need to use a picture hosting site, other than Photobucket. You picture is loaded and kept there and you access the image code bring it here and add to your post.

Honestly I have no idea what you are talking about lol I'm not old but I'm 47 and stuck in the 80's lol I never got into and no interest in computers, the game consoles like xbox and such. I will piddle around on this smart (dumbass) cell phone a little that the teen boys got me to replace my outdated flip phone lol. But I will get one of them to do it for me.

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Hell I don't even know how to work a cell phone. Never owned one and won't be a slave to one. 

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Times like this cell phone is good to have but other times not having one sounds good. Wife gets pissed off cause I won't answer it lol.

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Friday I took the alternator in to the shop and he rebuilt it and I picked it up same day which was awesome. So it still has the orginal 1985 Nissan alternator just rebuilt. The relays I got from Rock Auto. One was on clearance for $5 and the other for $6 and I was very lucky because I got the last ones. Oriellys was $25.99 plus $6.99 shipping EACH. I laughed at him. GUYS, CHECK OUT ROCKAUTO.COM FIRST some things are the same price but most is dirt cheap and is delivered super fast.

Thank you so much everybody.

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Did the chatter go away?

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Yes sir. The clicking, chattering and the crazy acting battery dash light is out and all. Shop guy said he didn't see how the truck even crank cause the alternator was so fried. I told him a new Exide battery lol and not drove that much till it was all fixed. The next morning I woke up sick as a dog and couldn't even get out of bed so the boy drove it yesterday to work and it did great until he ran out of gas lol I told him "get to walking that I told you to go straight to gas station" he said "just kidding I'm getting gas and truck is good but I still want something a little faster" yep I hung up on him lol

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