Bad Td Relay
Thread Starter
5th Gear
Joined: Dec 2021
Posts: 5
Likes: 0
Bad Td Relay
Having problems with my 97 c5 and jumped out Tdr (4 Prong) and it started. Tried buying a replacement and all I can find are 5 prong plugs. Can I use the 5 prong in my plug? It has an extra plug marked 87a?
Racer
Joined: Oct 2021
Posts: 389
Likes: 76
From: Chicago
Yes 87a is use for something like blinkers back and forth from ecm or bcm.
Melting Slicks
Joined: Sep 2008
Posts: 3,132
Likes: 799
From: Espanola New Mexico
Can you hear the TDR click on when you turn the key to crank the engine over? Brief explanation of starting circuit, 12v leaves the Ignition switch goes to the Park safety switch, and then the positive side of the TDR coil. The BCM provides a ground to the other side of the TDR coil if VATS is OK.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,508
Likes: 4,000
From: Cape Coral, Florida
Just try your local Chevy dealer...these relays aren't more than $20.00...4 bladed relays are very common...don't know why you had trouble finding one ??
Thread Starter
5th Gear
Joined: Dec 2021
Posts: 5
Likes: 0
