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U1000 Diagnostic Trouble Code Discussion for May 2008

Class 2 Communication Malfunction


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Trouble Ticket Help Requests for DTC U1000
Help Request Posted
2003 Chevrolet Malibu 3.1L No Start VIN: 1G1ND52J83
U1000: Class 2 Communication Malfunction. hello all and again thanks in advance on this one. It is a very intermittent no start but cranks every time. Every time it won't start it acts like the anti-theft activates. It will try to start then quit and just crank. Before changing the key and tumbler wit...
May 03, 2008
2003 Oldsmobile Alero GL 3.4L No Start VIN: 1G3NL52EX3
U1000: Class 2 Communication Malfunction. This problem has been very difficult to diagnose as it occurs very intermittently. Today it did it twice which was the first time in 4 days. When the problem occurs the green/white wire from the pcm to the fuel pump relay goes dead, no fuel pump. At first I th...
May 05, 2008
2002 Oldsmobile Alero GL 3.4L No Start, INTERMITENT VIN: 1G3NL52E12
U1000: Class 2 Communication Malfunction. vechile sits outside in sun for a period of time. the complaint is that it wont start and the door locks keep on unlocking and locking. when it stops the vechile will start. there are 5 codes due to loss of communication. plus in shop it will not start then tu...
May 14, 2008
2002 Nissan Altima SE 3.5L MIL Lamp on VIN: 1N4BL11E92
U1000: Controller Area Network Line Malfunction. We have checked every ground, module and connector on this car and could not find short or open. BCM circuit Check says if resistance is correct replace BCM and Intelligent Power Distribution Module says the same thing. We were slightly hesitant to replace the...
May 16, 2008
2006 Pontiac Grand Prix 3.8L Hesitation, Cuts out, Stall, MIL Lamp on, reduced power VIN: 2G2WP52261
U1000: Class 2 Communication Malfunction. The problem only occurs during heavy rain. Loses control over elec throttle. Cannot duplicate symptom in shop. Replaced APP sensor, found corrosion in C101 (frt of L strut tower) and repaired. No joy. Am aware of TSB for H2O intrusion at L kick panel area - no...
May 27, 2008
2003 GMC Envoy SLT 4.2L MIL Lamp on VIN: 1GKDT13SX3
U1000: No state of health from module. Hey Guys, I have this 2003 Envoy with a U1000 code that keeps resetting under both PCM & IPC. Vehicle came in and customer stated that MIL light was on but went off on the way over to us. For the P0128 code I'm going to replace the thermostat. The U1000 co...
May 28, 2008
2003 Chevrolet Malibu 3.1L No Start VIN: 1G1ND52J83
U1000: Class 2 Communication Malfunction. hello all and again thanks in advance on this one. It is a very intermittent no start but cranks every time. Every time it won't start it acts like the anti-theft activates. It will try to start then quit and just crank. Before changing the key and tumbler wit...
May 03, 2008
2003 Oldsmobile Alero GL 3.4L No Start VIN: 1G3NL52EX3
U1000: Class 2 Communication Malfunction. This problem has been very difficult to diagnose as it occurs very intermittently. Today it did it twice which was the first time in 4 days. When the problem occurs the green/white wire from the pcm to the fuel pump relay goes dead, no fuel pump. At first I th...
May 05, 2008
2002 Oldsmobile Alero GL 3.4L No Start, INTERMITENT VIN: 1G3NL52E12
U1000: Class 2 Communication Malfunction. vechile sits outside in sun for a period of time. the complaint is that it wont start and the door locks keep on unlocking and locking. when it stops the vechile will start. there are 5 codes due to loss of communication. plus in shop it will not start then tu...
May 14, 2008
2002 Nissan Altima SE 3.5L MIL Lamp on VIN: 1N4BL11E92
U1000: Controller Area Network Line Malfunction. We have checked every ground, module and connector on this car and could not find short or open. BCM circuit Check says if resistance is correct replace BCM and Intelligent Power Distribution Module says the same thing. We were slightly hesitant to replace the...
May 16, 2008
2006 Pontiac Grand Prix 3.8L Hesitation, Cuts out, Stall, MIL Lamp on, reduced power VIN: 2G2WP52261
U1000: Class 2 Communication Malfunction. The problem only occurs during heavy rain. Loses control over elec throttle. Cannot duplicate symptom in shop. Replaced APP sensor, found corrosion in C101 (frt of L strut tower) and repaired. No joy. Am aware of TSB for H2O intrusion at L kick panel area - no...
May 27, 2008
2003 GMC Envoy SLT 4.2L MIL Lamp on VIN: 1GKDT13SX3
U1000: No state of health from module. Hey Guys, I have this 2003 Envoy with a U1000 code that keeps resetting under both PCM & IPC. Vehicle came in and customer stated that MIL light was on but went off on the way over to us. For the P0128 code I'm going to replace the thermostat. The U1000 co...
May 28, 2008