DRL's DON'T work
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DRL's DON'T work
Anybody have a 98 DRL wiring diagram? I brought a 98 coupe to Canada from the US. It was originally sold in Mexico (next stop Greenland?).
When I picked it up none of the brake/signal/emerg lights were working. I took it to a dealer who said the hazard flasher was not working,replaced it and all seemed fine.I never thought to check (didn't care) that the DRL's were not working but upon inspection here in Canada (where if they don't work you don't drive it) found that they were not. #2 fuse and both relays(38 and 40) are good(no manipulation of contacts inside)and the e-brake switch works as it should (light on dash on when lifted,off when down).Pulled the relays and checked the panel with a voltmeter: terminal 5 hot always,4 hot when appropriate signal light on,3 will turn on proper light when jumped with 5 (as these 3 terminals should?)BUT terminal 2 is never hot (should it not be hot in RUN) and terminal 1 is always hot (should it not be hot ONLY when ebrake is on or headlights are on?). Is there a DRL module? Where? or is it controlled by the BCM? Thanks
When I picked it up none of the brake/signal/emerg lights were working. I took it to a dealer who said the hazard flasher was not working,replaced it and all seemed fine.I never thought to check (didn't care) that the DRL's were not working but upon inspection here in Canada (where if they don't work you don't drive it) found that they were not. #2 fuse and both relays(38 and 40) are good(no manipulation of contacts inside)and the e-brake switch works as it should (light on dash on when lifted,off when down).Pulled the relays and checked the panel with a voltmeter: terminal 5 hot always,4 hot when appropriate signal light on,3 will turn on proper light when jumped with 5 (as these 3 terminals should?)BUT terminal 2 is never hot (should it not be hot in RUN) and terminal 1 is always hot (should it not be hot ONLY when ebrake is on or headlights are on?). Is there a DRL module? Where? or is it controlled by the BCM? Thanks
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They are? The owner's manual states "...the DRL system will make your front turn signal lamps come on when...". If they were separate bulbs then why do those opposed to having them come on not just pull the bulbs instead of going through the complications of isolating the contacts in the individual relays? Does anyone know if there is a DRL module and where it is? Thanks
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Thank you SpeedyZ!!! You are indeed 4 Star Gold! This helps tremendously. Based on this it would seem I have some wires crossed/disconnected OR the wrong relays - they are OMRON 12077866. Are they correct?
You might want to watch for that!
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Did the PO inhibit the DRLs by fixing the relays?
https://www.corvetteforum.com/techti...=273&TopicID=1
The A2 fuse is the only temporary fix. The bulbs are dual function. Theres a live for T/S, one for DRLs and a common ground. Both bulbs would have to be blown to cause a total DRL failure.
https://www.corvetteforum.com/techti...=273&TopicID=1
The A2 fuse is the only temporary fix. The bulbs are dual function. Theres a live for T/S, one for DRLs and a common ground. Both bulbs would have to be blown to cause a total DRL failure.
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No, both relays check out. I tried them in my 97 Silverado and the truck relay in the vette. The link to the Germany how-to shows that by jumping CKT15 to CKT1315 and CKT14 to CKT1314 accomplishes exactly the same thing as pulling #2 fuse (it disables all CKT2740's and nullifies any effect by CKT1976 and CKT1966 leaving only CKT15 connected to CKT1315 and CKT14 to CKT1314). My problem is that the outer CKT2740's on the diagram should always be hot yet they never are on mine. And CKT's1966 and 1976 from the BCM should only be hot in response to input to the BCM from the signal light flasher or headlamps (the diagram doesn't show any input from the ebrake switch so I assume it must come from the Exterior Lights Cell somehow) but mine are hot all the time. Also CKT's 14 and 15 should be hot whenever the flashers and/or the headlamps (or ebrake?) are on but mine are only hot with the flashers. It's a problem unto myself, I'm afraid.
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Update in case anyone else follows this thread and is mislead by my first entry. It's OK (normal) that #1 terminal on the relays are always hot and #2 is never hot. I had been comparing them to my 97 Silverado DRL system that has them the opposite way but the coil inside the relay works either way (to connect 3 to 5 to power the front signal lights for DRL). My problem is that the BCM (which controls the DRL feature) is not providing ground to the #2 terminals when it should-either because the BCM is bad, is getting bad info from elsewhere (eg doesn't think the ignition key is on ?) or is misinterpreting the data. The car is from Mexico originally-perhaps when the BCM was programmed it wasn't told to turn on the DRL's when the ignition is on? In any case, I'm not going to replace it or have it reprogrammed. I think I'll put in an aftermarket DRL kit designed for the C4.
Incidentally there is an ERROR IN THE HELM SERVICE MANUAL for the 98 I found today. The pinholes on the C2 connector to the BCM are numbered incorrectly on pages 8-465 and 466. They should be C1 to C16 from left to right on the top row and D1 to D16 from left to right on the bottom row. Watch out.
Incidentally there is an ERROR IN THE HELM SERVICE MANUAL for the 98 I found today. The pinholes on the C2 connector to the BCM are numbered incorrectly on pages 8-465 and 466. They should be C1 to C16 from left to right on the top row and D1 to D16 from left to right on the bottom row. Watch out.
