Low Fuel and High Coolant Temp warning lights
- brokencase
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Re: Low Fuel and High Coolant Temp warning lights
What do you plan to do with the signal generator?
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Re: Low Fuel and High Coolant Temp warning lights
He needs to advance the (currently nonfunctional) odo reading in view of a looming smog test.
YMMV
Descartes: "Cogito Ergo Sum"
Lijewski: "Sum Ergo Drive-O. Mucho!
Lijewski: "Sum Ergo Drive-O. Mucho!
- brokencase
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Re: Low Fuel and High Coolant Temp warning lights
Oops, some how I skipped over that part of the discussion...
Anyhow here is a similar signal generator board to what was mentioned in the other thread...fully assembled.
https://www.ebay.com/itm/192001544024
Anyhow here is a similar signal generator board to what was mentioned in the other thread...fully assembled.
https://www.ebay.com/itm/192001544024
Specialization is for Insects
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Re: Low Fuel and High Coolant Temp warning lights
Thanks for the heads-up, Brokencase, better deal than most on Amazon. Found a few 120V/2a adapters as well. I already have one with various pin tip diameters, but not the little splitter connector. Would be nice to find a little splitter by itself, but seems too small an item. Might have to check out electronics stores.
- brokencase
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Re: Low Fuel and High Coolant Temp warning lights
John, just to clarify - speedometer works and odometer does not? Just want to make sure your problem is not bad Vss sensor in transmission, which often fails.
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Re: Low Fuel and High Coolant Temp warning lights
Yes, good speedo, no odo. Plus, the two warning lights seem to have their own schedule to light up; couple days on, one day off, etc.
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Re: Low Fuel and High Coolant Temp warning lights
Ha, here I thought the pulse generator was a board you had to build yourself (have no time for that). I ordered that and a 120v-2a adapter.
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Re: Low Fuel and High Coolant Temp warning lights
Still waiting for the components to arrive, but... now all the warning lights will come on (as if you're putting the key to KOEO) for a few seconds. Definitely loose connection or wacky voltage regulator?
Re: Low Fuel and High Coolant Temp warning lights
Hmm, all warning lights? In my case when it happened they all came on and stayed that way. After a changed the onboard computer it reversed to normal. Maybe it is a loose connection after all.
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Re: Low Fuel and High Coolant Temp warning lights
Which computer? The PCM EEC-IV, or is there something on the IC circuit board?
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Re: Low Fuel and High Coolant Temp warning lights
Under the upper dash (easy removal) above glove box is the module. I posted earlier how I found that the upper dash, when installed, can push forward towards the windshield and pressure that module's harness, the wires of which are bent 90*. I found on one occasion that o be the source of an IP issue with the lights on the right hand side. IIRC Dean (Brokencase) jerred at that suggestion...but as we all know, with Merks nothing seems to be forever problem free. I repositioned the module and harness slightly and, as Dean would say, it's been Scorpio Bliss since (~2 years of daily driving).
YMMV
YMMV
Descartes: "Cogito Ergo Sum"
Lijewski: "Sum Ergo Drive-O. Mucho!
Lijewski: "Sum Ergo Drive-O. Mucho!
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Re: Low Fuel and High Coolant Temp warning lights
OK, thanks Ed. Do you find its most often simply harness issues as you described, or best bet to swap in a new module?
- brokencase
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Re: Low Fuel and High Coolant Temp warning lights
Hang on a sec John.. They are all supposed to light up for the first 5-10 seconds or so when the car is first started. The purpose of which is so that you can tell if a warning bulb is burnt out.john keefe wrote: ↑Fri Mar 04, 2022 12:52 pm Still waiting for the components to arrive, but... now all the warning lights will come on (as if you're putting the key to KOEO) for a few seconds. Definitely loose connection or wacky voltage regulator?
They then all turn off after a few moments, with the ABS taking much longer to go out. The brake warning goes out upon first application of the brake pedal.
...and yes, at this moment I am in Scorpio Bliss....other than the car needing a wash and wax...which I may do this weekend.
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Re: Low Fuel and High Coolant Temp warning lights
Well, you already got advised on the computer location. I will add that once the dashboard is taken out, it is easy to reach and remove. There are two silver boxes in the area, the one in question is on the top, called Auxiliary Warning Module, shown on page 99 Electrical Manual. But Brokencase is right, the warning lights do come on with start up and stay for a second after ignition. ABS yellow light is the last one to go off, it takes about 20 seconds. Concur on the brake lights, they go off when you press the brake pedal. Perhaps a simple exercise to disconnect the module and spraying the connector with CRC electronic cleaner might alleviate the problem.
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Re: Low Fuel and High Coolant Temp warning lights
So I'll dive a bit deeper into my experience.
I've learned from years of experience that for disconnecting the IP from its harness, to not break the red or green or both printed circuit plastic mounting blocks, it's best to remove the upper dash first. Voila, you have excellent access to those blocks.
After acquiring my '89 over 2 years ago I removed the IP to install new odo gears and stepper motor. After reinstalling the IP and upper dash some of the auxiliary module functions didn't display. I removed the upper dash again and with it removed, turned the key to power up the panel, and, then found that wiggling the wires at the connector end everything displayed properly. So then I loosened the aux module, and fiddled with its frame mount to get a scoche more clearance between the upper dash and the module when the dash is installed. Then powering up the IP everything displayed and has continued to do so (it's my daily driver).
The reason for John's IP flaky displays could be something else. But be assured that on reinstalling the upper dash, the forward plus slight downward pressures to move the dash under and into its clip below the windshield could impinge on the integrity of the aux module harness pins' "purchase" into the module itself.
YMMV
I've learned from years of experience that for disconnecting the IP from its harness, to not break the red or green or both printed circuit plastic mounting blocks, it's best to remove the upper dash first. Voila, you have excellent access to those blocks.
After acquiring my '89 over 2 years ago I removed the IP to install new odo gears and stepper motor. After reinstalling the IP and upper dash some of the auxiliary module functions didn't display. I removed the upper dash again and with it removed, turned the key to power up the panel, and, then found that wiggling the wires at the connector end everything displayed properly. So then I loosened the aux module, and fiddled with its frame mount to get a scoche more clearance between the upper dash and the module when the dash is installed. Then powering up the IP everything displayed and has continued to do so (it's my daily driver).
The reason for John's IP flaky displays could be something else. But be assured that on reinstalling the upper dash, the forward plus slight downward pressures to move the dash under and into its clip below the windshield could impinge on the integrity of the aux module harness pins' "purchase" into the module itself.
YMMV
Descartes: "Cogito Ergo Sum"
Lijewski: "Sum Ergo Drive-O. Mucho!
Lijewski: "Sum Ergo Drive-O. Mucho!