I have and 01 duramax and I think I have a glow plug relay that has gone south on me. Was just wondering if anybody knew the location of the glow plug relay on the engine. Thank you for any suggestions.

driver side/rear of engine near fire wall. black plastic box/three big wires/red one is hot/boots on them that look like small 90 degree spark plug boots. if your throwing a po380 code and it is intermittent, check your connections.

Thanks for the info, that was the problem. One of the relays was bad. Replaced and is working fine.