Big Easy Sharkster

I previously reported clicking noises coming from the console on going over bumps or moderate braking. This noise sounds exactly like when you move the HVAC selector switch between vent options. I had the car up to a mechanic last week and he checked all vents and all opening and closing normally. Then we drove the car together while he listened for the whereabouts of this clicking noise. Turns out that it appears to be the #10 relay (ignition). Other than this clicking noise the car runs fine.

Changed out the #10 relay and same still happens. Any ideas what this maybe?

'94 GTS 5 spd

Fabio421

The fact that it happens when you go over a bump or during braking makes it sound like a loose connection somewhere. Maybe a ground? Does the engine stumble or change RPM when this clicking happens?

Big Easy Sharkster

Nope, engine runs fine. No stumbling. Does sound like a loose connection someplace. I might get a click or two going over a bump, but on a good braking, it clicks rapidly

soupcan

#10 meaning X? X would be the blower motor I think, IV is ignition on a 94.

Big Easy Sharkster

Hello Brian,

yes, #10 = X, sorry, I should stay with correct numerals

The electrical panel cover board has a description of relays and fuses on the backside. I don't have it here in front of me, but I do remember that it was non-descriptive, for relay 'X' ie I believe it said 'relay X' and no other description. When I go to the 928 Sp site, which seems to have the updated info, it says 'Ignition'. By the way, I do happen to remember that #25 fuse was the interior lights, and yr picture above shows it at #24.

WallyP

Relay IV is Relay X.
Relay X is the "Fresh Air Blower".

Clear? No?

OK - Relay IV is called Relay X, and is basically a slave to the ignition switch. That is, it is triggered by the ignition switch, and powers what would be called "accessory circuits" on an American car. Its function is to lower the electrical load on the ignition switch.

Relay X, using the standard nomenclature, is the blower relay.

If Relay IV is chattering, one possibility is a faulty ignition switch; another is a faulty connection behind the Central Electrical Panel or on the ignition switch; another is a faulty ground.

Big Easy Sharkster

Wally,

sorry for delay in responding...

I'm confused... let's use the 928 Sp fuse relay chart for 92-95 GTS's as reference.

Relay IV is 'fog lights'
Relay X is 'ignition relay X'

While I was driving the car and doing rapid de-acelerations, the mechanic put hands on all the relays and after several times, said that relay # 'X' was the chattering one.

I changed out relay X with a 'used but good' with no change. This week-end I'll pull the CE panel back and see if any loose connections.

Any chance the 'engine overheat relay' mounted on the engine computer frame (as referenced on the 928 Sp website) could be the culprit? I have never seen this relay before..

Thanks

dr bob

The relay in position "X" on your car is used only to block operation of the fog lights when the key is not in the engine-run position. See coordinates E8 for the relay, and D89 for the connection to the starter solenoid wiring from the starter relay (automatic cars) or the jumper in your 5-speed car. That relay might chatter if the connections from the ignition switch circuit 15 (on with key in engine run position) or the connection to circuit 50 (on when key is in engine start position) are poor. I'd look first at the 14-pin connector for the front-of-engine harness, a common place for corrosion from rain and car-wash water. Clean all the connections there with a soft brass brush. A weak connection there in the 50 loop to the starter will often pass enough current to get the starter solenoid to pull in, but may have enough resistance to keep the solenoid coil from grounding the "supply" relay in position X. Cleaning the connections at the starter itself will help too.

The factory's method of controlling the Supply X relay is kind of obtuse. The 'logic' to drive this coil exists on the X bus already. It would have been a lot cleaner to use that X bus signal to drive the supply relay coil, with the other side of the coil at ground (31) potential. That would have eliminated the potential (sorry...) for 14-pin connector or starter solenoid connection problems.



For those playing along at home, earlier cars ('89 and older) have a relay that duplicates this function, called the X relay. In the earlier cars, the X relay supplies power to the X bus, which supports various other light and accessory needs. On this GTS, power to that X-bus is supplied through a dedicated part of the ignition switch with no interposing relay used. The change seems to coincide with the addition of DRL capabilies, starting with the 1990 model-year cars.

Big Easy Sharkster

Thanks Bob

I had the 14 pin connector open a few months ago when troubleshooting the inop fan but didn't individually clean (these connectors seem to be looking for any excuse to get 'get out and get mixed up'). I'll get back in there and do a proper cleaning

The starter motor is new 2 mos ago, but probably should check connectors to make sure nothing has backed off.

Many thanks the good suggestions.

Big Easy Sharkster

Just to update, I took apart the 14 pin connector and cleaned as best as I could. After reinstalling, I've taken her out on a couple of short runs and clicking has stopped. Will continue to monitor and advise if it comes back.

Thanks to all who inputed into this thread

dr bob

Good news! Now find some high ground to store the care safely for the next few days. of course...last time I was in your neighborhood, the only available "high ground" was the top of a phosphate tailings pile a bit south of Lakeland.

Stay dry, be safe, and glad your problem was solved.

Big Easy Sharkster

Interestingly enough, I had the car at work (downtown Tampa) which has a covered parking garage with 5 levels, with intentions to leave there this week while I'm up here in Boston on Vacation. However the Republican National Convention is in town and with my office right in the middle of it, and all the 'crazies' running around town, I reconsidered and elected to take chances with 'Isaac' rather than the Anarchists. Watching the weather, a storm surge of 3-5' is predicted and I should be fine.

This car was with me for 'Katrina' in '05 and she spent 3 weeks in a 7th fl parking garage downtown New Orleans while we tried to get back into town to retrieve. Good sea story to tell on that one sometime over a beer.

coach928

I was diagnosing some relay issues in the dark last night and forgot to reinstall Relay IV. The car ran fine without the relay. I only noticed that it wasn't installed because it was floating around in the passenger area. What accessory circuits does this power? The fog light seemed to run fine without the relay installed and the key in the ACC position. Of course I reinstalled the relay, but I'm curious what I was missing when it was not installed.

Michael Benno

Interesting, I had the same exact issue happen to me recently with growing frequency. I too started with testing the vacuum actuators and supply lines for leaks... non-found. Grounds checked. Positive leads checked at battery, CE, and Jump post. Last night the clicking rose to a crescendo and the following items stopped working: Fogs, HVAC blower, Rear Defroster. But oddly the engine ran fine, headlights, blinkers, wipers, radio all worked fine. It seems the problem is limited to about half of the car system. I will start with the 14-pin connection. I recently had the FOE off for the timing belt job so maybe the connection between the socket and pin got out of tolerance. It seems to be vibration related since I cannot replicate the issue stationary.

Did the OP fix to the 14-pin connection resolve the issue?

Could someone help me understand what is "wearing out" in the ignition switch?

Bertrand Daoust

Make sure that the 14 pins connector is clean and tight (you can "open" the male connectors).
I fixed a day running lights problem this summer (clicking relay) this way.
At the same time, I'm quite sure I fixed air bag warning messages (on rough roads) that I had for many years.
Time will tell but I'm quite confident I fixed the problem. At least for now...

Worth a try for sure.