MH77280Z

Getting back on this topic, with car at normal operating temp and vent on Heat and full hot my fan DO NOT blow hot air 🙂 Does that mean air it not getting to the heater core? door not working? or water **** jam? my level is freely moving from COLD to HOT and i do see movement at the watercock (external connector etc.) Where to start? also do u think the two in cabin hoses can be serviced without taking the blower motor out?

So far 3 years I have not received anything asking me for a smog test here. Not sure why but on the registration card my car being 1977 280z is documented as 76 manufactured. I just saw this part on ebay and thought to get it. Car doesnt seems to have any problem running. Worst case it is passing some gases out which could have been recirculated! thats how i understood the operation of this valve.

I meant it blows same amount of air both directions. It is supposed to be one-way and i did the water test as well.

My original do not hold pressure one way so I think it is bad. Seems like this is same part as the one u are referencing.

Here u go, CA models only. Most cars I have seen here has bypassed this. Goes between thermal vacuum valve and BPT valve.

Not replacing anything yet but just inquiring if anyone has used this. There is a similar valve on the 280z correct?

Hi guys, Has anyone tried this part? or any other alternative? I think there is a similar GM valve as well which I can share later (cannot find it at the moment...) https://www.ebay.com/itm/263537911654

@jfa.series1 thanks for the pics they help. I have a toggle switch like the one top right in the lower radio. This connects to a 3-pin connector. My question as i mentioned above where does the wire from the OE antenna connects into. Yet to explore my under dash properly.

Yes, it seems to be an aftermarket antenna. I googled the original one and that has a 3 pin connector attached to it with a body mount bracket. One available on ebay for $3000 😇 (someone wants to take it with him to the grave). My question was there has to be a 3-pin wire coming to the OEM antenna to connect to. Where in the dash that wires comes from. (i do have a 3-pin outlet where i can install a 3-pin toggle switch). Does it make sense? a picture would be useful.

Yes

I know where the operating switch can be. I am talking about where the original antennas 3 wires connect into? Is there some switch under the dash where the wires connects into from the antenna.

OK so seems like mine is not original as well. It is a replacement. BTW where is the original antenna switch located where the 3 wires hook into?

I traced the wires and there are only two wires GREEN/RED coming out of the antenna (also one thick signal cable). Electric wiring diagram shows three blue wires at the antenna?

Hi Guys, The car i bought has some custom work done on the stereo and OEM antenna. The 3 blue wires with a switch do not work. How does the antenna normally work on the 280z? I mean the switch has two positions and I would expect it is an UP/DOWN operation and the antenna can be stopped at any position (i mean half up vs full extended) can someone confirm? Currently it is connected to the stereo/radio and when i turn the unit on it just fully extends automatically. May be thats why the switch does not work.

Hi Guys, The car i bought has some custom work done on the stereo and OEM antenna. The 3 blue wires with a switch do not work. How does the antenna normally work on the 280z? I mean the switch has two positions and I would expect it is an UP/DOWN operation and the antenna can be stopped at any position (i mean half up vs full extended) can someone confirm? Currently it is connected to the stereo/radio and when i turn the unit on it just fully extends automatically. May be thats why the switch does not work.

OK, so while I was planning to test the BY lead like @SteveJ mentioned the engine cranked up fine to my surprise. I did not modify anything, I was seeing the issue last night when I left the car. I suspect that I am having issue with the inhibitor switch as my A/T selector lever has some play. I tried again starting the car with the A/T lever in R and D and the car did not start and i hear same clicking in ignition relay. The car right now is starting fine in the P and N position. I am about 80% sure it is inhibitor switch acting funky due to this play in the level. Planning to lift the car to tighten it and inspect the switch. Manual says PINs on switch should have continuity at P and N. I really appreciate everyone hanging in with me.

OK so the reverse / R rear lights operate normally. Here is quick voltage check: Ignition Relay: I see 11-12 volts on all 3 wires going to relay in START position Seat Belt Relay: Sees 12v at WB terminal only So basically there is no 12V in BY (black yellow) wires coming from Seat Belt relay to Starter terminal.

Shorting the two going to the start circuit would not be any issue I think? That’s what the switch is supposed to do in N and P anyway?

How many wires go to the inhibitor switch? i have not looked under but I was thinking is it safe to connect both and bypass the switch?

Just an update for you guys, I got the replacement ignition relay today and tried it with the same result. No change. Issue is somewhere else now...

Just tried this procedure on the new ignition SWITCH (pic above) and same effect. What is the best way to test the seat belt relay function here?

@Zed Head u r right the remote starting works just by supplying 12v to the pin. Other jumper is not needed. Also, i tested the voltage at the positive terminal of the coil (assuming ignition coil): - At ON there is no voltage - When I move the key to START i see 12v Appreciate everyone patience so far guys. I think we are not far away from getting to the issue... Also, why do u say the ignition relay is not in the starter circuit? The FSM page i posted clearly says there are 3 parts of the starter circuit Starter Relay, Ignition Relay (not Module - correction) and Inhibitor switch.

It ran after I bypassed the ignition relay with a remote starter switch only. I was having this issue intermittently before when sometimes the ignition relay just used to click vs sometimes it worked. This time I believe it gave up altogether and now I am all up to remote starter only.

Yes the voltage was tested at ON. I have not replaced the ignition relay. I do expect a used one coming in next week. let me try measuring the voltage coming into the relay. As I suspect it is ignition relay causing issue.

Tested voltage to ground at on and start at this black white wire in the white connector - left bottom wire and seeing nearing nothing like 50-60 milli volt on the meter.