No Throttle Response, Elec Malfun And Abs Light On

[brian529]

2002 CH613 350/385. Hoping someone has seen this problem before. Out of no where the truck will hiccup. No throttle response at all. When this happens the Electrical Malfunction Light and the ABS come on. Brought the truck to Mack, they pulled the codes and came up with a bad EUP. This was replaced and and off I went. On the way home it briefly hiccuped for a split second and then was fine for about 500 miles or so. It did it again and I cleaned the connections on the positive and neg blocks on the firewall and it was again good for about 1500 miles. Friday it did again no throttle response, Elec Mal Fun and ABS light on and also would not shut off (1 time). When this happens the idle stays aroud 600 sometimes rising to 800. After about ten minutes and starting and shutting the truck off 2-3 times it magically was fine. I made it the 212 miles home without a hitch. This is the third time this happened. Can't afford to be stranded. The truck is back at Mack today. Any help would be appreciated. Thanks.

[QCDriver]

I had that problem. It turned out to 1 bad rear ABS sensor. Did it agian like yours. I took some ABS SAFE BRAKE Clean and cleaned the rest. Sovled my problem. Hope you get yours fixed.

My left front still throws a code every now and a agian, but has not went into safe mode cutting power. From my experience it goes to safe mode if it's a rear ABS ( but that is my guess).

[rhasler]

I had that problem. It turned out to 1 bad rear ABS sensor. Did it agian like yours. I took some ABS SAFE BRAKE Clean and cleaned the rest. Sovled my problem. Hope you get yours fixed.

My left front still throws a code every now and a agian, but has not went into safe mode cutting power. From my experience it goes to safe mode if it's a rear ABS ( but that is my guess).

Yes I've seen this happen with ABS sensors too. In our case the tip of the sensor was rubbed through causing the seonsor to short intermittantly when the teeth on the tone wheel passed it. Always reset the sensors when you have the opportunity (sometimes they freeze up in the mounting brackets and can be a real pain). Just push the sensor all the way against the tone wheel on the hub and it should be ok (this helps to keeps them from freezing up in the mounting bracket). The sensors will self adjust from there. Remember to clean the tip of the sensor and the tone wheel as well.

[brian529]

Thanks for the responses. The problem was a harness issue. There was a short in the dome light wire. The following codes were present- 6- SID231 FMI8 15X EECU, 6-4 SID FMI 8 3X VECU, MID136 SID231 FMI8 ABS. Followed service bullitin SB221032 cleaned power and ground connections and measured voltage drop. Contacted Mack tech support and was instructed to follow ABS J1939 Data cable. Found a chaffed and shorted wire under dash along side of J1939 data link. Repaired wiring and ran a new J1939 data cable overlay harness linking the ABS,VECU AND EECU together. Wired in and secured. I put on about 3k since repair and the truck is functioning properly. Hope this will help someone in the future.

[rhasler]

Thanks for the responses. The problem was a harness issue. There was a short in the dome light wire. The following codes were present- 6- SID231 FMI8 15X EECU, 6-4 SID FMI 8 3X VECU, MID136 SID231 FMI8 ABS. Followed service bullitin SB221032 cleaned power and ground connections and measured voltage drop. Contacted Mack tech support and was instructed to follow ABS J1939 Data cable. Found a chaffed and shorted wire under dash along side of J1939 data link. Repaired wiring and ran a new J1939 data cable overlay harness linking the ABS,VECU AND EECU together. Wired in and secured. I put on about 3k since repair and the truck is functioning properly. Hope this will help someone in the future.

Glad you got it fixed. It's sounds like you probably didn't have to spend too much to fix it either.

[brian529]

Total cost was 400.00. I thought I'd pass on the knowledge to help save the cost for someone else. Thanks for your suggestions.

[parks truck]

I have a 98 ch613 in the shop with intermittent electrical problems blink code 6-4 already replaced data link harness in dash still having problem also have abs code that says abs warning light bulb current below normal or open but I cant find abs light